AMENDMENT NO. 1
                                        TO 
                              STOCK PURCHASE AGREEMENT


     THIS AMENDMENT NO. 1 TO STOCK AGREEMENT dated as of March 31, 1999 by and
between Zenith Insurance Company, a California corporation ("Seller"), and
Nationwide Mutual Insurance Company, an Ohio mutual insurance company ("Buyer").

     WHEREAS, Seller and Buyer are parties to a Stock Purchase Agreement dated
as of February 22, 1999 (the "Agreement"); and

     WHEREAS, Buyer and Seller desire to amend the Agreement;

     NOW, THEREFORE, in consideration of the premises and the mutual terms,
conditions and other agreements set forth herein, intending to be legally bound,
the parties hereby agree as follows:

     1.   Section 2.2 of the Agreement is hereby amended by:

          (a)  substituting the amount "Two Hundred Seventy Five Million Six
     Hundred Thirty Nine Thousand One Hundred and Sixty Dollars ($275,639,160)"
     for the amount "Two Hundred Seventy-Two Million Dollars ($272,000,000)" in
     the first line thereof;  and 

          (b)  substituting the following sentence for the second sentence
     thereof:

          "The Purchase Price shall be subject to adjustment after
          Closing pursuant to Sections 2.4 and 2.6 hereof."

     2.   Section 2.3 of the Agreement is hereby amended by and restated in its
entirety to read as follows:

               "The consummation of the purchase and sale of the
          Shares ("Closing") shall be effective at 11:59 p.m.,
          California time, on the last day of the calendar month in
          which all conditions to the respective obligations of the
          parties set forth in Sections 7 and 8 hereof (other than
          those that are intended to be satisfied only at the Closing)
          have been satisfied (such effective date and time being
          referred to herein as the "Closing Date").  The physical
          transfer of funds and delivery of the Shares shall occur at
          11:00 a.m., New York time, on the Closing Date at the
          offices of 




          LeBoeuf, Lamb, Greene & MacRae, L.L.P., 125 West 55th Street, New
          York, New York, or at such other time, date and place as shall be
          mutually agreed upon by the parties.  Each party hereto agrees to use
          commercially reasonable efforts promptly to satisfy the conditions to
          Closing to be satisfied by it in order to expedite the Closing."

     3.   Section 2.4 of the Agreement is amended by substituting the phrase: 
"an unaudited statutory balance sheet of CalFarm as of the Closing Date (the
"Closing Date Balance Sheet")" for the words "an unaudited statutory balance
sheet of CalFarm as of the end of the calendar month immediately preceding the
Closing Date (the "Closing Balance Sheet")" in the third line thereof.

     4.   Section 2.5 of the Agreement is hereby amended by: 

          (a)  substituting the words "Within the earlier of 15 days after
               receipt of the 1998 Pro Forma Balance Sheet or 9:00 am (New York
               Time) on March 31, 1999" for the words "within 15 days after
               receipt of the 1998 Pro Forma Balance Sheet and 
     
          (b)  amending the last sentence thereof in its entirety to read as
               follows:  

               If Buyer does not notify Seller as to any disputed items within
               the earlier 15 days after receipt of the 1998 Pro Forma Balance
               Sheet or 9:00 am (New York Time) on March 31, 1999, the 1998 Pro
               Forma Balance Sheet provided by Seller shall be deemed acceptable
               to Buyer."

     5.   Section 2.6 of the Agreement is hereby amended and restated in its
entirety to read as follows:

               "On March 3, 1999, Seller provided Buyer with a copy of an
          appraisal report prepared by Giannelli, Jarrette & Filipiak on the
          real property located at 1601 Exposition Boulevard, Sacramento, CA
          95815 (the "Sacramento Property") which set forth an estimated current
          market valuation for the Sacramento Property equal to $24,155,000 (the
          "Appraised Value").  On March 16, 1999, Buyer delivered notice to
          Seller of its objection to and dispute of the Appraised Value (the
          "Objection Notice").  Buyer shall deliver to Seller, within 30
          Business Days after the delivery of the Objection Notice, at its own
          cost and expense, an appraisal report by an MAI certified appraiser of
          Buyer's choice familiar with the Sacramento commercial real estate
          market, of the estimated current market value for the Sacramento
          Property 


                                         -2-


          (the "Buyer Appraised Value").  If Buyer and Seller are unable to
          reach agreement as to the amount of the purchase price adjustment, if
          any, due under this Section 2.6 within 15 Business Days after receipt
          by Seller of the report containing the Buyer Appraised Value, Buyer
          and Seller shall select another MAI certified appraiser familiar with
          the Sacramento commercial real estate market with no material
          relationship with Buyer, Seller or any of their respective affiliates
          to render a third appraisal report of the estimated current market
          value for the Sacramento Property (the "Final Appraised Value").  Upon
          determination of the Final Appraised Value and within two Business
          Days after delivery to Buyer and Seller of a copy of the third
          appraisal report, (i) Buyer shall pay Seller, in immediately available
          funds, a sum equal to the amount, if any, by which the Final Appraised
          Value exceeds $20,000,000 and (ii) Seller shall pay Buyer, in
          immediately available funds, a sum equal to the amount, if any, by
          which the Final Appraised Value is less than $20,000,000; provided
          that in no event shall Seller be required to pay Buyer an amount in
          excess of $3,639,160."

     6.   All other terms and conditions of the Agreement are hereby ratified
and confirmed by the parties hereto and shall remain in full force and effect.

     7.   All capitalized terms used herein and not otherwise defined herein
shall have the respective meanings provided such terms in the Agreement.

     8.   This Amendment shall bee governed by and construed and enforced in
accordance with the laws of the State of California, without giving effect to
principles of conflicts of laws.

     9.   This Amendment may be executed in two or more counterparts, each of
which shall be deemed an original, but all of which together shall constitute
one and the same instrument.


                                         -3-


     IN WITNESS WHEREOF, the parties have executed this Amendment as of the day
and year first above written.

                                   ZENITH INSURANCE COMPANY


                                   By:  /s/ John J. Tickner
                                        -------------------
                                      Name: John J. Tickner
                                      Title:   Senior Vice President


                                   NATIONWIDE MUTUAL INSURANCE COMPANY


                                   By:  /s/ Robert A. Oakley
                                        --------------------
                                      Name: Robert A. Oakley
                                      Title:  Executive Vice President -
                                              Chief Financial Officer


                                         -4-