Tubular upper arms-I feel lucky tonight

gussets are not required when using the correct materials for the design and then welding those materials properly.

http://www.inertiamotorsports.com/camshafts.html
http://www.progressiveautomotive.com/IFSparts.htm


and a very interesting design here:
http://www.hotrod.com/techarticles/chassis/hrdp_0706_camaro_frames/photo_05.html