Jonseys,

Your setup sounds fine.

During my initial build I used standard thread cap head screws for the engine and used the longer metric set through the firewall and put metric nylok nuts on the back, up against the metric blind nuts. I did have a landing gear screw strip out once (also metric and same size as others).

42etus brought this thread back to life from 2006, but if you want, check out my original Edge 540 thread here:
[link=http://www.rcuniverse.com/forum/m_4303162/anchors_4303162/mpage_1/key_seagull%252Cedge%252C540/anchor/tm.htm#]http://www.rcuniverse.com/forum/m_4303162/anchors_4303162/mpage_1/key_seagull%252Cedge%252C540/anchor/tm.htm#[/link]

You might also be able to pick up some tips from my website's build page (see sig. below)