Plan on adding about to 3/4 to 1 oz. of weight to the right wing tip to offset muffler. Laterally balance the plane with all equipment installed, but before you cover. I did and this plane flies beautifully thru all pattern sequences. Knife edge has no coupling tendencies, snap rolls are same both right and left.
If you look close you can see the two 1/8 oz split shot sinkers I added (crimped on "T" pins, CA'd and then the pinspressed through the bent and PVA glued in place both sides). But I'm balancing a much smaller aluminum 4-stroke muffler (pointing straight at the camera in the image). I'm the headless guy in the white shirt.
I covered in yellow & black & orange trim top (and all orange under the wing panels).
Flew out from under my canopy last time and I have to add some screws!