1979 Econoline350 needs help!
 

My van has been in the family for over 27 years now. It has an 8 cyl. 460 with only 70,000 original miles on it. It has sat a lot over the years but with a little love starts right up. I have wanted to modify it for years and now can do stuff to it. I was hoping to get some suggestions on where to buy parts and figure out how much I can really do to that 460. Can I put chevy pistons in there? What's the best place for performance parts? Please bestow some knowledge on me!!