273 auto trying to find the 'tick'

you are going to use your bell for a bracket pattern?
Yes, I believe this would be the best pattern. I am not sure why he doesnt just bolt it up....tough to get to bolts?

Sure it's not an exhaust leak?
It might be, but when I heard it I ran my hands around the manifolds and didnt feel any puffs....I wish I had taken a video. I will during the next startup though.

Ill report back. Ill try to have more pictures. Its really only half a story without pictures. I should know better.