New to the board and a Couple of Questions

[bad72c10]

Hi guys, just found this board, and it's awesome!!
I have a '72 Chevy C10 SWB. It has a 350 bored .030 over, so I guess a 355 and a TH350, but it is not the original motor or trans. It was a 350 with a 3 on the tree.
My first Question is about the Rear end in my truck. As I said it was originally a 3 on the tree with a 350, and I'm praying for a 3.73, but you guys are the experts.
My second question is about my motor. I am planning a Performer Cam and intake combo. I am also going to put heads on the motor and I have a set of 2.02/1.60 heads available to me. But, I also have a set of Powerpack heads available. What do you guys think of each? Thank you guys in advance, Justin