This is what I came up with:

create procedure MOD_UPDATE
as
begin
truncate table oradba.modmast;
insert into oradba.modmast (MBSEG,CO,PLANT,MODEL,WIDTH,LNGTH,HLNGTH,PRLIN#,MDLEDT,BEGCAT,ENDCAT,BASEPR,BASECS,FLRNUM,MODES,MODP RE,MODSUF,WOMOD,AUTUPD,LSTUPD,BOMNAM,UPDDT8,AUDDT8,CRAP,FASTNR,MSPRF1,MSPRF2,MSPRF3) values (select * from plmprod.modmast);
end
/