csisfun:

We have about 50 spads at our field and they come in at all sizes and shapes.
Most of the guys build with the yard stick main spar and balance at this point. Of course we do have a few that like to prop hang and these guys go just a little tail heavy. But like in the previous post I would recommend balance as close to the main spar and then adjust to your liking from there.

Miloh.