Magnum use longblock, carbed intake, electronic dist w vacuum advance. Somebody correct me if im wrong here but use LA waterpump and pulleys. You can even use 5 bolt valve covers on 10 bolt magnum heads if you like old skool look. Use V8 k off parts car or keep your slanty K and use schumacher motor mount adaptors from slant 6 to 360. Carb your choice. I prefer AFBs. Some like Holleys. If engine is not center sump. You will need to buy a 360 center sump passenger car center sump oil pan and oil pick up tube. A 318 car pan wont fit a 360 and vise versa.
Trans. I dunno. Maybe use the magnums O/D trans and fab up a trans mount and beat the dickens out of your trans tunnel to make it clear, and cut the car driveshaft to fit. I hear these are bretty big. Or just use a torqueflight A904 3 speed that fits and may not have to cut down your existing slanty shaft.
Oh your stock 7.25 rear will go boom with a V8. So swap an 8.75 if you have the money, or swap in a furd xploder 8.8 out of a an explorer sport trak. Its got big bolt pattern, 5 bolt 4.5" circle. Rear discs, 3.73 gears and a locking diff. All for around $200 at a pick n pull near you
( this rear is nice when upgrading to discs in the front from an M body same bolt pattern.)
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