It butchers the car... why do that? Most guys that put them in for header clearance use headers that would fit with the shock towers anyways.

It's not an ideal setup, the rack interferes with proper engine location. The angle on the steering U Joint is usually severe. Most installations i've seen are poorly thought out, the rack sits so high they raise the engine or lower the whole suspension so it hangs way below the frame, then use drop spindles to get the car back to stock height... from the front it looks as though the car ran over a jack or something.

If it's to clear a big block there are better ways. The whole shock tower can be moved outwards 1" and welded back in. the lower control arms get moved out too. In my opinion if you wanted to make an "FX" appearing car, and had no tool smaller than a crescent wrench for the header bolts (can't think of any other reason why the shock towers need to be completely gone) you'd be better off with a straight axle, at least it looks like it belongs.