it sounds like bill was saying the VW lifters or smaller...so bushing the lifter to size work work, they have a wide face on them=''mushroom''.
i think u need to install them from the pan side of the block. fwiw
the smaller header tube 1 1/2 of the mp moves exhaust faster, though i wonder about a 1 1/2 to 1 5/8 stepped primary tube header would do...
