Well, I'm definitely keeping the 120 now. My LHS wouldn't exchange it because it was a special order. He's a very small operator an I'm glad he can stay in business. It's probably a good engine choice anyway.

I looked at the plans for a third time, and if I use separate left and right beam mounts, I can put the carb right next to the firewall with a very small clearance gap. With this set-up, the prop washer is only about 1/4 inch forward of plan. That's probably not enough to worry about.

Next question is, if I have to, how do I mount my battery pack in the tail. Do I make a sort of battery pack mount/hatch cover and screw it to the aft fuse structure? Suggestions here are welcome.

BTW, I do anticipate balance problems primarily because I like to fly with the C.G. at the aft most position. I find this to result in the most honest flying airplane for aerobatics.

Thanks for the support.