I Have a 68 302 short block in near perfect condition (heads are shot from a poor long block we bought). I have a good 302 from an 89 lincoln with roller cam. I am trying to figure this out on my own but need some help, nobody around here knows how to piece one together. So I bolt the heads on the block and have figured out so far that the roller cam motor pushrods are about 3 inch short. The 68 pushrods colapse the lifter all the way down so the rocker arm must be different on the roller motor. I got some rocker arms of an earlier motor and tried them, they work better but tighten up slightly compressing the lifter ( i guess due to the heads probably being milled). I think what I need to do is get screw in studs and use the original adjustable rockers. My question is, will that work? Is that the best fix?
I also am guessing that compression will not change enough to matter, everything is stock. Original heads are 58 cc and lincoln heads are around 63 or so using a syringe and plexiglass.