I also have one of these I picked up from a guy with no manual. Another problem solved thanks to RCU.

With an MDS 28 up front (with Spinner) I came out with a CG of 3.5" back from LE. Way nose heavy. I had to mount the RX batt way back in the tail. Mounting that was fun. I had to build some special tools out of dowels and music wire to hold the batt back there while I attached some velcro to the bottom of the tail. Even with the batt that far back I have a CG of just over 4" back (the batt is an AAA NiMH that doesn't weight much). I think the last guy hated it because he said it flew poorly. It may have just been real nose heavy.