Sorry Joe but I don't know enough address the differences between different rockers. I know that real TA's have offset rocker so there's little chance mistaking them and assuming that might be a solution is not valid at this stage of troubleshooting.
Has the cam been changed? Was it converted to solid lifters from hydraulic? You said you previously used 3/8's push rods which can be problematic in a small block without additional work to clearance the larger diameter. That may very well be what really happened. Do you know what length they were? What length Proform push rods did you buy? Between the Proforms website and Summit they have 7.19, 7.35 & 7.5 inch lengths available in 5/16 cup/ball configurations. How did you determine which length to buy?
Slow down and don't jump to fixes until you now what you have now. Seriously, get some push rod length checkers and find out. Only then can you determine the next step. Start at the beginning, one step at a time.