I think the original measurement put the carb on a 2 stroke sticking out in front of the cowl when it was all mounted. It made you cut way too much of the front out.

My suggestion is fly it before you get to carried away chasing a CG point. Use some stick on weights so you can change it around easily, then move the battery as needed. I always went for a setting that gave good knife edge flight, then for me everything else felt good. My CG was most likely a little ahead of what most people put theirs on, but, I didn't try to turn it into a 3D machine either.

Ed M.