[NotchJohnson]

1. You need 351 swap headers.
2. You need a 351 swap oil pan and pickup.
3. You need a different lower intake. If you dont wanna go all out, you can get the lower off of a 5.8 truck motor and your stock upper will bolt to it.
4. Your fuel rails can be reused, you just need to extend the crossover tube to accomidate for the wider lower intake of the 351.
5.You need a new distributor.

Pretty much everything else is interchangeable, Ive heard you need a different a/c - p/s bracket, but Im not sure about that one. Also I just saw where you said you bought the motor which 520hp, so I assume there are already heads on it, otherwise you would have to drill yours to accomidate 1/2in head bolts. Thats all I can think of right now, maybe someone else can chime in if I missed anything, John.