Hi Dan,
The Argus is a beautiful stunt plane. It is on the slightly *small* side, smaller than the Ares, any of those engines would work just fine if you don't go way overboard on the finish weight.
Aaron flew his Ares for years on a *pre-owned* Randy Smith OS32F at 36 oz. The RH T&L 40 is a real *grunter* for an older engine, and the Brodak has plenty of power for that design. We used a 10-4 1/2 B-Y&O on the OS 32. (just check the pitch on the B-Y&Os, and use the lighter *5* pitch ones.
) Prop clearance might be an issue if the original LG length was used for the kit. Steve used about 9 1/2" props on his first one.
I bent the gear slightly longer and left the wheels on the same vertical plane, used both the L&J Fox 35 and the DS 40, both with a Veco extension, on my plans built Argus.
Mongo