Well, I carefully unwrapped my xmas gift box to pull out the plane one more time while the wife was away, I can definetly see the angle in the firewall that I was wondering about, I held my DLE-30 engine with the Jtec wrap around pitts muffler up to it, looks like I may need about 1/8" spacer even with the standoffs that came with it so that the muffler will not be touching the firewall, I guess that will move the prop a bit past the recommended 6-1/4", it will end up being almost 6-1/2", hopefully this isn't a problem.  Since it has already snowed and I won't see grass till April, I bought a set of skis for the plane, I quickly checked how much ground clearence I would have (with skis) and 19" prop is tight, but I think it should work.  I'm thinking I am going to switch the nylon clevises with the Dubro Kwik Loc type - are they any good?</p>