The Suby rack is about an inch longer than stock overall. I tried to line up the LCA pivot point with the tie rod pivot (with wheels straight). That point is about 1" up and .5" out. I had just enough adjustment with the AZC lower controll arms to make it work. I have camber plates up top so camber adjustment wasn't a problem. I never tried this setup with stock LCA's in stock location, but I would expect bump steer issues.
If people are having problems with the ford rack it may be that they are not addressing this problem by moving the pickup points of the LCA.
It would be interesting to compare overall length of the mustang rack to the Subaru, and to a stock rack.
If someone could measure a Mustang rack, I will measure the Subie and a stocker. (tie rod pivot to tie rod pivot)
Dave.