I don't think there will be an issue. The struts truly set the dihedral. There will be enough movement in the wings to allow for a minimal amount of dihedral. If needed we could make an adjustment to the ribs and make some ply rings to glue and permanently set the dihedral, as we discussed today. From all the photos I have seen there there appears to be about one degree of dihedral in most Cub wings.

I put one degree per wing in my Cub just to make sure I don't have the wings drooping. My 1/5th Scale Cub has less than that.

I just saw your post.. 3/4 of an inch over a 140 inch wing is tiny. We cant change the inner ribs, because they set the alignment of the wing to the fuselage, so we would have to make the adjustments to the outer ribs with the wing tubes. Likely open up the hole down towards the bottom of the ribs allowing the wings to rise. You will find this will be minor, like 1/8" to 3/16".

Phil