Ive also found some interesting differing features on these trailers from the information in the manuals.
In both SB-8 and SB-8A the body description has the fender brackets being riveted to the fender and bolted to the body. However in the Box Opening and Chassis/Body Assembling instruction it mentions using 26 3/8-24 x 3/4 hex head bolts to mount the fender brackets to the fenders and the body. The pictures in the manual show rivets whereas my trailer has bolts.
Another difference is a change of master cylinder. SB-8 in the parts listing has a part # of 91A-2140. This is a master cylinder with a 1-1/6" bore for a Ford 1/2 ton pickup. Whereas my trailer has the larger cylinder with a 1-1/4" bore for a Ford 1-2 ton truck. Looking over the picturs in the manual you can make out a difference in the reservoir height between the 1/2 ton and 1-2 ton master cylinder. So obviously both were used but only the small is listed.
Lastly a bit of a mystery item that doesn't show up in the parts listing or the wiring diagram. An extra side mounted tail/stop light. This was in the SB-8A manual only.
