Thanks guys. Summary of the week's work:
It seems that the only way anything fit on this model is to clamp. All interfering points have been removed to get the wings on, yet it still needed me to glue the front first, wait overnight, then clamp and glue the rear.
Though I had set the clamps to make the surface between the fuselage and wings more or less flush, it seems that the plastic crept over time and this required that some putty be applied to fill in the area,
With the wings on and the dihedral correctly set, I cut the leading edge slats out so that they could be displayed in the deployed position. Look how thick the frickin' plastic is!
With that done, the nacelles were installed using clamps yet again.
Big, ugly gaps between the nacelles and the mating wing cutouts.
The slat areas were filled with sheet styrene and then shaped. The top front and rear joints of the nacelle to the wing needed to be filled with CA glue and smoothed out. Then, a preliminary coat of primer was applied to see what has yet to be done.
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Not bad for the first pass. Lots more filling, sanding, and rescribing to be done. I'm also toying with dropping the flaps as well.