My Dad an I each built a goldberg extra with the northern light trim scheme mine has a ST.90, and his has a .91FX both great preformers. other than a fiber glass cowl, there isn't much to change. We used a Dave Brown fiber glass pushrod system on the elevator with 4-40 hard ware. keep the wire landing gear! they really keep the shock and stress away from the fuse, and if the ever get deformed, they can be replaced for a buck a side!