Looking for some basic info on swapping a roller motor(1996) into my '68. Thought someone who has gone carbed might have some info. The question concerns the timing cover, timing chain and fuel pump eccentric. I realize I need to go to a timing cover that allows for a mechanical fuel pump. I'm looking for a true roller timing chain. Some say they work with a two piece eccentric and others say they work with a one piece eccentric, additionally others just list date for production. So, which do I use? Thanks for the input.