Doing one right now, standard factory 304 and parts in a 74.
Front crossmember and mount brackets off a V8 - must have.
Have to change wiring for alternator as they are on opposite sides, same for coil power and oil sender wire. Water temp sender can stay.
Fuel line is on wrong side to match up with the fuel pump so has to cross over somewhere.
Exhaust manifolds:- later header free flow type on steering column side, have to use early 'log' stype dogleg on other side.
Trans dipstick is a pain, still working on it.
6 cyl crossmember OK.
I put in a 8 3/4 AMC diff; driveshaft needs shortening about 1". Parts book says six cyl and V8 are different, so maybe just the length. Stayed with the 904.
Minor stuff like vacuum lines to brake booster, if you have power steering then the V8 pump is on the opposite side too. Shorter hoses.
Mine had a floor shifter, linkage lined up OK, no changes.
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