I'm looking for a 350 with the one piece rear seal,four bolt main,and factory rollers. In which vehicles would these be most common? I know that the older style 350's with 4 bolts / forged crank were usally in vettes and heavy duty trucks.

 

for a 4 bolt block with a one piece seal and factory roller's i'd recomend looking for a truck or van block from a 1996 through 2002 with 8600gvw rating or higher. you can also look for a more difficult to find 4 bolt L98 block, but i don't recall what year they began making them. i believe it was around 89 or 90 for y body only, but that could be incorrect. i can look that up at work and will this week.