hemi.. sierra advertises here on RCU often.. you can probably find him by just doing a search within this site.... and your numbers look pretty good to me. The difficulty with the gear is that the mustangs gear pivots near the strut in the foward section of the wing.. most retracts pivot farther back so they dont mount as close as they should to be absolutely scale.. the only person I know who makes retracts like that is Ultra precision.. the retract valve guy. He makes/made a set that went between the ribs (from front to reat) and used a gear to operated the strut.. it was for a larger scale mustang.
I would stay with the one piece wing because of the inner gear doors.. I guess you could engineer it as a two piece and make it all work. its just more work.....Regards BobH.