Be creative with the cutting, and remember that what you can't see at three feet can't beseen at 300' either (bascially, seams are OK, because no-one except yourself will see them).

Just thinking about it, though, what you are saying is that the wing width is just over half the width of the covering. My suggestion....:
use small/thin pieces to cover the trailing edge and inside of the aileron pocket, ending in a straight line about 1/4" in front ot the ailerons. All that is now left to cover are the top, bottom, and leading edge of the wing.

So, cut new roll of monocote in half length-wise to cover the top of the wing to within about 1" of the leading edge. The other half covers the bottom. Now you need to cover the leading edge. From the first roll that had the pieces used to cover the trailing edge, cur the leading edge strip, that neatly overlaps the top and bottom with wind-resistant seams, over fully sheeted areas (the leading edge is sheeted, right...).

So far, used 1 roll for the one wing half, with about half a roll of small bits here and there. We also have a fair amount of scrap left over.

Using another complete roll, and the scraps from the first wing, you could probably cover the other wing. Three rolls instead of 4 is a good thing....

The point is, there is nothing wrong with covering the trailing edge first, then the tops, and bottom, then the leading edge.

Basically, cover with 4 panels on each wing, but do them the other way around (from root to tip, instead of TE to LE).

gus.