V8 hydraulic lifters

Kim, I think the early RBs used the short lifter and the pushrod with the tapered tip on it. IIRC it's 68-up use the same lifter, but the OP may be looking at two different recommended lifters for the same grind cam... Small blocks may want the "Hi Intensity" (anti-pump-up) lifter rather than a stock type with some cam profiles.