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                                                                     EXHIBIT 8.1

                 [SMITH, GAMBRELL & RUSSELL, LLP LETTERHEAD]


                                 March 4, 1997



F.N.B. Corporation
Hermitage Square
Hermitage, Pennsylvania  16148

West Coast Bancorp, Inc.
2724 Del Prado Boulevard South
Cape Coral, Florida 33904

         Re:     Agreement and Plan of Merger under which West Coast Bancorp,
                 Inc. will merge with and into Southwest Banks, Inc., a
                 wholly-owned subsidiary of F.N.B. Corporation

Ladies/Gentlemen:

         We have acted as special counsel to F.N.B. Corporation ("FNB") in
connection with the proposed merger (the "Merger") of West Coast Bancorp, Inc.
("West Coast"), with and into Southwest Banks, Inc. ("Southwest"), a
wholly-owned subsidiary of FNB, pursuant to the terms of and as described in
that certain Agreement and Plan of Merger (the "Merger Agreement") dated as of
November 15, 1996 and as amended on February 28, 1997, by and among FNB,
Southwest and West Coast, described in the FNB Registration Statement on Form
S-4, to be filed with the Securities and Exchange Commission on or about March
4, 1997 (the "Registration Statement").  At your request, in connection with
the filing by FNB of the Registration Statement and the Proxy
Statement-Prospectus of West Coast and FNB as amended through the date hereof
(the "Proxy Statement-Prospectus") included as part of the Registration
Statement, we are rendering our opinion concerning certain federal income tax
consequences of the Merger.  Unless otherwise indicated, all capitalized terms
used in this opinion have the same meaning as used in the Proxy
Statement-Prospectus.

         For purposes of rendering our opinion herein, we have conducted an
examination of the Internal Revenue Code of 1986, as amended (the "Code"), and
such other applicable laws, regulations, rulings, decisions, documents and
records as we have deemed necessary.  With respect to factual matters, we have
relied upon the Merger Agreement, including, without limitation, the
representations of FNB, Southwest and West Coast set forth therein, and upon
certain statements

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and representations made to us in certificates  by officers of FNB and West
Coast, in each case without independent verification thereof.  With the consent
of FNB and West Coast, we have relied on the accuracy and completeness of the
statements and representations contained in such certificates and have assumed
that such certificates will be complete and accurate as of the Effective Time.
We have also relied on the accuracy and completeness of the Proxy Statement-
Prospectus.  In addition, for purposes of this opinion, we have assumed that at
least fifty percent of the outstanding West Coast Common Shares will be
exchanged for FNB Common Stock in the Merger, and that the West Coast Common
Shares constitute capital assets in the hands of each holder thereof.

         Based on the foregoing, and subject to the qualifications set forth
below, we are of the opinion that under the Code:

         (1)     The Merger will constitute a reorganization under Code Sections
368(a)(1)(A) and 368(a)(2)(D), and FNB, Southwest and West Coast will each be 
a party to the reorganization within the meaning of Code Section 368(b).

         (2)     Holders of West Coast Common Shares who exchange such shares
solely for shares of FNB Common Stock will not recognize gain or loss on the
exchange.

         (3)     The federal income tax basis of shares of FNB Common Stock
received in exchange for West Coast Common Shares will be equal to the holder's
basis of the West Coast Common Shares surrendered in exchange therefor, and the
holding period of such FNB Common Stock will include the holding period of the
West Coast Common Shares surrendered in exchange therefor.

         (4)     The receipt of cash in lieu of fractional shares will be
treated as if the fractional shares were distributed as part of the exchange
and then redeemed by FNB, and capital gain or loss will be recognized in an
amount equal to the difference between the cash received and the basis of the
fractional share of FNB Common Stock surrendered.

         The opinions expressed herein are based upon our interpretation of
existing legal authorities, and no assurance can be given that such
interpretations would be followed if the exchange of shares contemplated by the
Merger became the subject of administrative or judicial proceedings.
Statements of opinion herein are opinions only and should not be interpreted as
guarantees of the current status of the law, nor should they be accepted as a
guarantee that a court of law or administrative agency will concur in such
statement.

         No opinion is expressed with respect to any of the following:

         (i)     The appropriate method to determine the fair market value of
any stock or other consideration received in any sale or exchange;

         (ii)    The state, local or foreign tax consequences of any aspect of
the Merger; or

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         (iii)   The federal income tax consequences of any aspect of the
Merger to holders of West Coast Common Shares who are subject to special tax
treatment for federal income tax purposes, including among others, life
insurance companies, tax exempt entities and foreign taxpayers, or to holders
of West Coast Options which are exchanged for or converted into options or
warrants to acquire FNB Common Stock.

         We expressly consent to the filing of this opinion with the Securities
and Exchange Commission as an exhibit to the Registration Statement, and to the
references to this opinion in the Proxy Statement-Prospectus.  In giving this
opinion, we do not hereby admit that we are in the category of persons whose
consent is required under Section 7 of the Securities Act of 1933, as amended.

                                           Very truly yours,             
                                                                         
                                           SMITH, GAMBRELL & RUSSELL, LLP
                                                                         


                                           /s/ David W. Santi
                                           -------------------------------------
                                           David W. Santi                

DWS:jeh