Upright or inverted?
I prefer inverted on a low wing, as some models carry alot of mass above the thrustline and become difficult to balance upright.
Many will argue this, doesnt matter though, I've never had a model(nearly 100) that was way out on CG and all have flown with sucess.

The weight needed, you are describing, seems unlikely for this small model. The tail is a bit long on that Cap, and the nose is short.
Hope it helps. let us know.

If the servos are in the tail, moving one or both will make a huge difference on this model.