Right, it seems to be a common theme with Van's: once they drill the hole for you, or you drill the hole yourself, well, that's it. There is no adjustment. On the 7A, the main wheel strut towers and the struts themselves are already drilled. You ream them to final size, but don't really affect the geometry. You just hope that the hardware has been produced to the tolerances that are needed: caster, camber, toe-in/toe-out they are all non-adjustable and set by the production process of the factory.
Another area that comes to mind is the aft wing spar hole. We set the wings for incidence and fore/aft sweep and of course edge distance. Then you drill the hole, hope that it is square, and the wing is set - no adjustment. If that hole is mis-drilled, how in the world would you fix it?
Well, that is the nature of our world of Experimental/Home Built.
Cheers and Blue Skies!