Some pics, in case it helps.

One (the one w/ the notes added) was something I found that Jim Hanrahan (440Jim) posted years ago. Looks like Jim's picture was taken w/ zero-offset lifters, but annotated to show where grinding would be needed to use offset intakes..

The others are from the mock-up I mentioned above. If you look closely at the #3 intake, you can see the masking tape I put on the pushrod is being torn off due to lack of clearance w/ the block boss. The intake pushrods were all really close, even if they didn't rub.