More on the inverted issue. I pulled the McCoy and put on the LA46. I think the plane gained 6 or 7 ounces in the process, all on the nose. As a result, I had to add tail weight, 3 ounces. Too much, the plane "hunted all over" during "level" flight; but, it did run inverted.
Now I have trim issues to resolve. The plane pulls great in level flight, but I loose all line tension at the top of the arc; I mean really lose it. I tried more engine offset, and while that increased line tension in level flight, it didn't help up top. I've been reading on the subject, and think I'll try moving the lead-outs forward. I've ordered an adjustable lead-out assembly from Sam's, so now I wait.
I put the old McCoy in what I refer to my "Rinkydinkmaster"; it's an old Ringmaster I flew back in the 60's and have "restored". The dang McCoy ran inverted on this plane! Not perfect, but surprisingly well. So well, I flew the complete pattern, albeit a very sloppy pattern, for the first time in over 37 years. As sloppy as it was, it felt good.
Brian