I was considering that as well myself. I decided to go with the LE of the wing, not the fairing. I've added 1lb. 7oz. to the firewall. All up weight is 20lbs.
My engine is the RCS 180se front carb gasser

I'm going to fly mine this Friday. I took it out to El Mirage last Friday but it was a bit gusty so I decided to wait. It's too pretty to mess it up because of impatience.

Overall I'm very pleased with all aspects on mine. I had what looked like scratching in the wing covering but after I re-shrunk the wings it diminished greatly to be a non-issue.

I relieved the LE guide pin hole ( fuse side ) of the lower right wing. No big deal here.

I used some black foam board to enclose the rear passenger compartment. Very light and it has a nice finished look