the slots are not for slotting but to allow wicking of CA into the body of the part.

Cowl sanding not much of an issue for me - just used a dremel along the seam then some wet and dry and a bit of T Cut - done.

Double skinning inner wing bays - didnt bother.... I just done let anyone touch the wings there and putting wings on and off is done by handling the tips.

Rear ele servos will not give you a problem... I have 2 x 9206 at the back and my battery in over the CG.

Gonna bench run my new 140 tonight I hope so its ready to try out on Monday when I come back from La France !