Up to late 1986 yes. After that year no.
Chevy had cross ram fuel injection in 1982 on their 305 camaros
All small block oil pumps will physically interchange with each other, before 2000. Keep in mind they make high pressure, and high volume pumps, as well. They are usually just big block pumps. Yeah, they are all the same.
If the Buick 305 is really a Chevy 305, then the motor mounts will interchange with a Chevy 350.
no
yes if they are both throttle body engines
Keep in mind the #1 problem with these vehicles is fuel pumps. Most of the time the regulator is replaced needlessly.
The headers for a 350 and 305 are the same.
YES they are the same.
No they are not.
in the fuel inlet on the carb.
Oldsmobile used to make a 307 V8, but it has nothing in common with a Chevy V8.