Quote Originally Posted by SS Killer View Post
I was under the impression that the lifters sat "ahead" of the cam center line, that way, the lobe pushed them in a more upward direction instead of relying on the wall of the bore to direct the lifter up. I could be wrong.

I had always assumed everything was in line untill a buddy of mine said otherwise... since then, I haven't been able to check.
Looking at your drawing, the lifter body could possibly make contact with the cam lobe. The lifter bore in the engine block supports the lifter from side-to-side and front-to-back.