you are now at what can be the trickiest thing about planes in general, Balancing. It is a pain and requires patience and time. The more you do it the better you get as far as where to start and how far to move things in order to balance. Did I read right you have no instructions for the plane? If you do have instructions then in the manual there should be a recommended range. Start at the front of the range and work back slowly till it balances. But stay in the range. You can even add weight to get it to balance but try to avoid it if possible. In my planes I do not like to add more than and 1 oz max. At this point I only currently have 1 plane that has any dead weight.

Do you have any kind of CG machine or the like? I use the GP CG machine and have never had a ill balanced plane from it. Very easy to use and cheap too if I remeber right.

Jason