Carbed Magnum parts list?

Good posts above.
Absolutely start with www.magnumswap.com . That site has nearly everything you'll need to know and it's hard to imagine that you'll walk away not wanting a Magnum motor. They're easier to come by than comparable LA motors and have a lot of benefits...not the least of which are the updated gasket designs that drastically reduce leaks.

One thing that hasn't been mentioned yet is the flex plate issue. If you have an automatic, you'll need to swap to a Magnum style flex plate with external balancing. It's not expensive...but really important. ;)

I have ~500 miles on my 5.9 Magnum swap now...so far, so good! I haven't had much tuning time but the thing starts right up and drives every time, no leaks, no trouble. No regrets here!!