RE: info on Sig Buster Kit parts
The SIG Buster probably used 3/32" wire for the landing gear. It was intended for 0.15 engines. 1 1/2" to 2" wheels, if you can find some very thin racing wheels so much the better. (Like Don's Wheels - looked like a pair of flat cymbals stuck together around the rim.) Could search on 'CL Racing' - there is a National CL Racing Association (NCLRA) site which might help. Those 2" Glenn Lee wheels might do real well for you.
The approximately 40" Buster profile was originally a Carl Goldberg kit. Had a built up wing; fuse and tail were sheet and slab profile parts. It has been rekitted by several guys, after the CG kits fell away. This one is for .36 to .40 engines.