Steering rack help....

I'd imagine width would be a major problem with the GM rack, you need something thats of a similiar or wider width, try a Scorpio/Granada rack, you will also find that the Mustang uses imperial taper on the rod ends instead of our Metric tapers, but a machine shop will sort that out easily enough.
other possibilities are maybeMercs or Jags with Racks

You have to hope the home brewed version is only in mock-up
The only doubts I had about the conversion I did was the steering arms never sat level with the rack, so any loading back from the road wheels had a sort of torque/shear action against the 2 bolts holding the plate in position as the 2 bolts were quite close together, 3-4 inches apart, I think if you could find a rack that had the bolts wider apart than that it would help with stability of the replacement center drag link,
Now I'm thinking off the wall here, using a traditional end fitting rear steer rack, remove the ball joints, make and bolt a finger for each end from flat stock facing forward or rearward depending on application, then weld a bar across the fingers, so you now have a bar that mimics the action of the rack. drill the bar so it has the same pickup points as the center drag link, mount the rack so the bar sits in the same place a the drag link, rose joint the ends of the steering arms so they can be bolted thru the bar and you should have a rack that mimics the CDL without bump steer, for applications where the steering shaft input is tight, there is no reason why the rack cant be moved over to clear the engine, and the plate on the rack be drilled with the equivalent offset to put the steering back to center ------------------now clear as mud---good ;D

yeah don't worry on the forum i got those of he is just mocking thinks up with those brakets, the rack he uses is of a US cavalier, which having googled it is a completely different thing..

I'll have to investigate the UJ angles, shouldn't be a problem though as hundreds of these cars have racks fitted without problem so there must be a successful way of doing it...
I think the main advantage of doing it this way is the original mustang geometry is largely unchanged as you are effectively replacing the box with a rack all the track rods and tie rod stay in the same position..

Can't be that difficult to get a LHD euro Cavalier rack from Germany or similar? The only other way to do it is to find a RHD rack that usually has the pivots infront of the ball joint. You could then flip the rack over the LHD and mount it in the Mustang position and it'd still work OK. If you do that with a rear mounted rack the steering feel and geometry would be fine, the wheels would just go the opposite way to the way you're steering lol.

Matt