The Magnum IIRC has dual mounts; both LA and truck. The truck mount sometimes has to be worked over to fit certain headers or exhaust manifolds.
The front of the engine, if from a truck, has a reverse rotation pump. If you get rid of the serpentine system, you can use all the LA stuff.
The mechanical fuel pump only works on the early non-injected Magnums due to different cams in the EFI models.
Magnums are balanced different from the LAs so the balancer and the flywheel have to stay with each respective engine.
Not all log-manifolds will work in cars, Trebleg has the scoop on those.
Magnums are a good choice. They have an advertised Scr of 9.5 and, together with their better heads, are quite a bit more powerful than LAs.
