Robert B.Gibson;of 1234 Hillcrest Ave.;Monessen;died Monday;May 31;1982;at 7:20 p.m.in Mon Valley Hospital following a lengthy illness.  He was 63.  Mr.Gibson was born May 25;1919;in Monessen;a son of Robert T.Gibson of Largo;Fla.;and the late Irene Scales Gibson.  He was employed in the Sheet-Mechanical Department of the Allenport Plant of Wheeling-Pittsburgh Steel Corporation until his retirement in 1981.  Mr.Gibson was a member of the United Methodist Church and the BPO Elks Lodge No.773;both of Monessen.  Surviving;in addition to his father;are his wife;Doris Yates Gibson;at home;one daughter;Mrs.David (Jane) Altemara;of Monessen;two sons;Robert W.Gibson of Belle Vernon and Mark Gibson of Monessen;one sister;Mrs.James (Geraldine) Beeler;of Keystone Heights;Fla.;and two grandchildren.  Friends will be received at the Rhome Funeral Home;Inc.;1209 Grand Blvd.;Monessen;at 9 a.m.Wednesday until the time of services at 10 a.m.in the funeral home;with the Rev.Kenneth J.Peters;pastor;United Methodist Church;Monessen;officiating.  Burial will be in Belle Vernon Cemetery.  The family suggests memorial contributions in Mr.Gibsons’s memory may be made to the Monessen Ambulance Service through the funeral home.  The Rhome Funeral Home;Inc.;is in charge of arrangements.