Well, I own a 102 Std III and have never had any real trouble with it,
but I think that the the most critical points are 1) having the right
spar position marked on the bulkhead and 2) having a 1-man rig. The
1-man rig allows the weight of the wing to be supported at the center
of the wing, so that there is no vertical load being supported at the
inboard end. Those loads are being supported by the pin fittings that
you are trying to get to slide togethor. They will slide better if
they are not under load.

Todd Smith
Grob 102
3S