Did you try contacting Ekstensive? Since you say you're running their front kit, they would probably be able to set you up with the best set of uppers, at least in terms of geometry. On their online store they only show uppers with standard ball-joints, but I'm sure they could make you a set with uni-balls in them. If they wont I would make an adapter bracket that mounts in the same location as the ball-joint on the Ekstensive arms but has a cup for a uniball. Would be a pretty simple piece to make imo.
Michigan Metal Works can make you a set with Uni-balls in them as well, but it is more probable than not that their geometry would be slightly different from that of Ekstensive, which is why i recommended contacting Ekstensive first.
If you can afford it just send your truck to Brett (Tukn4s) and let him set you up. He's one of the 2 people I would trust with my setup.
