Ken,
I have built that plane with bolt on wings. The rubber bands deformed the wings and fuse too much. They crunched the wings and fouled up the trim.
1) Use 1/4" nylon bolts. Pretty tough to shear, but buy extras and carry them with you anyway. If you really don't want them to shear use aluminum or steel. I however use and recommend nylon. Foam doesn't break, but a lot of the plane is not foam..
2) Glue 1/8" ply plates to the bottom of the fuse in the wing saddle. I went nearly full width and basicly square. "Countersink" the plates.
3) Standard single servo mounted in the wing is fine.
4) Use blind nuts (t-nuts, whatever they are called) in the ply to screw into.
5) Use 1-1/2" square 1/8" thick ply "washers" on the bottom to distribute the bolt load and prevent pull through and wandering. I did not glue mine on, but it might not be a bad idea to keep from misaligning the wings. Countersinking and gluing will definitely be smoother. Cover them the same color as the wing bottom.
BTW, I did mine in yellow sign vinyl with black stripes, stars and bars etc and black wing and stab bottoms. Looks good, flies well. A friend of mine recommended against silver after experience with a Mustang.