360 magnum swap?

We need more info. Are you going to use EFI? What kind, OEM? Megasquirt, Holley, other?

You going to go with carb? What manifold?

Belt drive? Serpentine? V belt? PS pump?

Headers/ manifolds? Pretty much a bolt in

Engine mounts? Pretty much same as your 360

What transmission? What engine CAME OUT? The balance on a FIVE POINT NINE (It is not a 360, that's an LA) is DIFFERENT that any other smallblock. So depending, you need a 5.9 flywheel, NOT a 360LA flywheel, NOT a 318 or 5.2 flywheel.

If this was an automatic, there are same issues

Isn't it fun guessing? Please post what you have, what you are going to, and what you have now to "go to that."