edmoor,

Did you line up the original leading edges, trailing edges, or neither? Your concern for tail moment is probably the biggest issue. If the bigger wing is farther back on the fuselage you could have a handful in pitch sensitivity. There might also be an issue with tail size ratio with the bigger wing. This will establish how sensitive the new arrangement is to CG location. If it were me, and it still looked about right, I would give it a go. Doesn't sound like you have too much invested in it anyway. Might be a fun flyer. Balance as required by the bigger wing.

I once took a clipped wing from a GP Trainer 60 and grafted it to a fuselage with the tail of a Nosen 40 sizes Citabria and had a blast with it.

Good luck!

Bedford