I put a G-20 in an H-9 Hellcat and yes, it was way more than it needed.

It would be interesting to see how it would work in a Skybolt. You would need to add tailweight to compensate, and it would increase the wing loading, but the Skybolt can easily handle a heavy wing loading - I had a YS 91 with a smoker in mine, so I know it would handle the weight.