The 305 is OK, here are the vehicles it has been in. 350 is good also. Keep in mind, though, the 305 should be cheaper than a 350 or no deal. They are not as popular and a you can get a running used 305 for $250-$350 around here and a 350 is $450-$650 generally speaking. So the rebuilt cost should be lower due to the "core" costs and popularity. It would not be real easy for him to get rid of the 305. But using a 305 is still OK. Hope you are talking about a V8 305 and not a V6?????? GMC had a 305 V6. Don't do that.
1976-1992 Chevrolet Camaro
1980 Chevrolet Corvette (California only)
1977-1993 Chevrolet Caprice (includes Impala)
1977-1986 Pontiac Parisienne
1976-1979 Chevrolet Monza
1976-1979 Chevrolet Nova (also GM X-body clones after 1976)
1976-1988 Chevrolet Malibu, Chevrolet El Camino, and Chevrolet Monte Carlo
1978-1992 Pontiac Firebird
1978-1980 Oldsmobile Cutlass (US Market only, Canadian market 1978-1987)
1991-1992 Oldsmobile Custom Cruiser
1981-1987 Pontiac Grand Prix
1975-1979 Buick Skylark
1977-2003 Chevrolet/GMC Trucks, SUVs, Vans
1991-1992 Cadillac Brougham
1978-1987 Buick Regal
