Bullet, I feel it's necessary to modify that which I said in an earlier post. On your triangulated links, the front pivot points are very close together. For this reason, I said you had nothing to worry about as far as binding is concerned. Than, cboy posted pictures of his setup. As you can see, his triangulated links are separated, at the back end, by the center section. The further apart the mounting points at the "peak" of the triangulation, the more bind will occur. Cboy has taken care of the problem by using rubber bushings. This is how Detroit takes care of it, too. These kits, however, usually use Heim joints, which are, of course, quite rigid. There's always going to be a little "give," of course, so some binding can be tolerated, even with Heims. Though the Heims are "pretty" pieces of hardware, don't feel that you have to use them. The Ramchargers used rubber bushings on the trailing links of their C/A.
As to why binding occurs: It only takes 3 trailing links and a Panhard to locate an axle. Any more trailing links can cause binding. Your upper links are mounted so close together, at the front, that they're essentially one large triangular link. In fact, if a single Heim could take the loads, it would be ideal to combine the links at the front and use one Heim. (I'm not saying you should do this, for that's a big "if.")
Anyway, this is another good reason for Morrison to show the links parallel in the side view. He doesn't want you breaking Heim joints with excessive deviations from parallel which cause higher binding loads (though still much less than with a conventional 4link).