I was stuck for quite a while up until recently with the Cessna model. I went to try to attach the wing to the body, and the body was too wide, and it made the wing too tight and not fit right. The body was apparently slightly too wide at that point, and so when I forced to fit, the wing tips bent up quite a bit.
Well, sitting outside last week for Haloween, I took some time and filed down the fuselage of the airplane so the wing fit better. Here you can see the marks above the windows:
After doing that, I managed to jury-rig the propellor onto the front of the cowling so that it's attached and turns, and then I get the cowling front attached:
Then I got the wing glued on, finally:
And the wing struts and main landing gear, so it's starting to look like a real airplane!