I'd get rid of the 10 bolt and get something stronger.

I think TSP has some of the best deals on already ported 5.3l heads if you are looking to upgrade in that direction.

Snow Performance or Alky control is good in the meth injection dept.

 

Dropping the 10 bolt is a no brainer, but I won't fix it til it's broke.

 

If u change springs go either patriot duals,lunati duals or I've heard good about Brian tooley but never personally used them

 

If u do heads either get a set of 5.3s ported or even a set of 243s ported