What would you do with the shock mount? It seems like that would have to move with the UCA mounts. And that might cause problems with the connection of the shock to the LCA.
Moving the mounts would give the option to use a stock UCA and still get 6 or 7 degrees of positive caster, but when SPC control arms do that for much less work it seems like the tough way to get there.
BAC/SPC 1.5 Upper Control Arm - Bergman Auto Craft