I added bolt on wing to an Eagle II and this wing also sits atop the fuselage. It was a bit of work on the leading edge but it can be done as the dowel needs to protrude down at 40 degree angles as opposed to straight out like normal. If your a builder and want to spend a few hours on it can be done but if your not a builder, I wouldn't recomment it on these type models as there is a bit of re-engineering to do.

For example you would need to add a secondary bulkhead at the leading edge inside the fuselage to better accept the downard facing dowel more properly. I only added one dowel in the middle, opening up the bottom center section and locating that dowel through to the wing joiner, sandwiched on each side by forward section ply replacement ribs with downard facing tongues to sandwich the dowel with filler top and bottom and the whole shabang wrapped in carbon fiber thread and epoxied. Its bulletproof but I probably wouldn't do it again. Just got tired of the rubber bands going bad over time, etc.