A simple trick that might make a difference is to paint the aluminum skin inside the fender with undercoat or flat black to camouflage the background with a non-contrasting color. It does look like they need to be lower, but if you go too far they will look like they are hanging off of the bottom of your wall; which could also be considered "stink bug".
I have a similar problem that I will have to address with my jeep style fenders on AT tires; they are too short length wise, kind of tall, and barely wide enough to cover the tread. When they are centered on the tread I have big gap between them and the wall. In my future I see either custom fenders or buying another pair to do lots of cutting and splicing (they are aluminum and nowhere near the organic shape of yours).
I like your wheel/tire combo, so for your fiberglass fenders (which I assume cost a bit and it would be a shame to wreck 'em), you may want to start from scratch and either sell or return those (maybe?). Maybe someone else will have a better solution.
It is very important, IMO, to get the fenders right. They can make or break the graceful lines in a big way, either way.
I see you got the FJ you were talking about!
