I port matched the heads and intake. Very little material removed. I polished them also.

I had an 89 350 that would oil foul a plug within 200 miles. It was from a worn valve guide. New seals didn't make much difference, but rebuilding the head fixed it.

I just rebuilt the engine, including head job and the problem started afterwards. 2 valve guides were replaced. The only thing I did differently was the Total Seal rings.

Wow why aren't your ring gaps the same for all 8 cylinders, I've never seen that much of a spread in the ring gaps.

The Total Seal rings have to be filed to fit. I used a ring file tool. I know they vary a little but they are all within the required tolerances. Also, they are gapless once you install the second thinner steel band.