YES, If you have center dump exhaust manifolds you will want to make sure that they will bolt up to the 350 heads. You did not say what year heads you are going to use. BUT more the likely they will bolt up.
yes they will bolt right on.
They will fit, but the engine won't perform very efficiently. Also, 283's didn't have accessory bolt holes on the ends.
a 350 is a small block those heads will fit on and Chevy SMALL block not a big block
yes all sbc manifolds will fit, when you get to cyl heads then you will have trouble since most aftermarket are for 350 bore which is larger
350 heads will bolt to the 400 block. They will need to be drilled for the "steam ports" in the 400 block.
the heads should fit as long as your not trying to put them on a big block
yep
As long as the 350 is older then a 1987, you will have no problems. They will bolt right on with no modifying.
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no
no they will not
Yes, they should fit ok. 305 heads should bump up the compression a little.