I was at the Junkyard looking at a roller cammed engine and a 86 SBC and it looked like the only difference in them is that the studs in the lifter valley of the 86 weren't tapped and the roller cam one obviously were tapped for the roller lifter girdle. I have a 86 350 in my 85 TA and want to make it a roller since I already have the one piece rear main seal. Since the 86 block is the first of that type of 1 piece seal then can I get the girdle, lifters and pushrods or is this not doable at all?

 

the tops of the lifter bosses are machined, i think, and the front of the block machined for the retainer.