I had the mark @ 2 1/2 in. instead of 3 1/8. i used a peice of tape to mark the cg and put it in the wrong place after i measured it,stupid mastake.I'm happy to say it only took 1 3/4oz. on the firewall to balance. yes, i balanced it inverted. Just getting back into the hobby after 6 years,so i consider myself pretty much a beginner. It's starting to come back to me. I have 3 airplanes, nextstar,decathlon 40,and the spacewalker. i have yet to fly any of them. been practicing on the realflight g3 sim. for 2 months now and going to join a local club soon. Thanks alot for all the input guys.