-ik-, the G10 was not even a development series, they were just upgrades of older G6's to bring them up to par with the K4. The g10 designation is a bit of a weird a/c to model since the upgrades began within a few weeks of the K4 near the end off 44.
As far as the engine is concerened, depending on which model pyro does, you might as well cal it a G14 or in the case of the "d" engine call it a K4. Unless, pyro is planning on blending the attributes of the two a/c rolled into one and calling it the G10, which IMO, isn't such a bad idea.