I just got my heads back from T&D 1.6 one shaft per cylinder. I had my indy rocker. My engines is a 400 block stroked to 500ci indy -1. Oil was block on the left side. Now I have the Isky 3772-LO-180 lifters that are suppost to oil the top. Do I have to take of the plug that restricted oil to the heads? Does anyone use these isky lifter and T&D lifter in a 400 stock block unbushed if so how does it work?