Hi Jack:

I ran the calculations on the exisitng kit suggested C/G of 5-1/4 in. and this turns out to be approx. 27% of the MAC as discussed earlier.

Therefore, to go to the Max. aft C/G, you can go AFT another 3/8 in. (5-5/8 total from L. E. at wing root ) which will yeild 30% MAC. DO NOT go more aft than this. I would only do this as a last resort. This location turns out to be the REAR edge of the Wheel Well in the Fuselage.

Yes, the kit supplied spinner adds significant nose weight to the completed model.

The only other suggestion I have is to put the batteries on another tray on the FRONT side of the firewall if at all possible, but I'm sure you have already thought of this.

Sorry I cannot be of any fruther help.