Just started my Seagull Gee Bee Z. Making my first post to this thread. I have read about 7 of the 29 pages of the thread so far and see nothing about engine thrust lines. My ARF kit seems to have no angle to the firewall so I am going to add 1.5 degrees down and 1.5 degrees right. I made a shim to bring the engine out to the right position and give it the angles. Going with a Saito FG-40 gasser on this Z running a 19 X 10 XOAR. It is going to cowl in nicely with the head down and maybe only the rockers protruding from the cowl. Leo