There's a point that I missed. Thanks! You're right--the ribs on either side of the retract and nacelle should be ply. Best option is to move the W3 ribs to these locations.

The mains are 5.5 inches tall. The wheelse are 2.5 inches in diameter. There's plenty of room between the first two ribs of the wing for the wheel and the 5.5 inches will put the retract in the right place. The measurements work out...

I'll sketch in the nose tomorrow.