RE: Rhom-air to electric conversion TF Spitfire
I can't be a lot of help but perhaps I can be of some... try looking into Lado electric retracts. I have a set but have only run them on the bench so far. They're realistic/slow to extend and retract. They look fairly rugged and if they happen to stall, they automatically shut down so as not to drain the battery. I think I paid about $200 for the set of two for my TF Mustang (whenever I get around to building it).
If you do use the Lado's, measure the retract pocket first to make sure that the Lado's will fit. I think I might have to modify/widen my Mustang pockets a little bit to make them fit but I could be wrong about that. I have seen other retracts by major manufacturers but they seem to be a bit more expensive than what I paid for the Lado's.
Just my $.02
Bob