I made my own, I swapped a V8 durango steering box in there and had to space it out a bit (3/4" maybe?) from the framerail so I took some 3/16" plate I had and drilled holes in it for the 3 steering box bolts then welded some solid metal cylinders (dug them up out of our shop that's been working on heavy machinery since the 60s, I have no clue what they were from) to the plate to space the steering box out from the frame rail. I did have to buy longer bolts.
The other side of the frame rail is 1/4" plate that runs into my front bumper where I have also made a new x-member to add stiffness to the whole thing (1/4 plate also on the outside of the other framerail so the front end is boxed in).
I sorta planned it out and wanted to make a new front bumper, tow points, steering brace and front end stiffener all at the same time and it ended up working great. This was on a '97 XJ but as far as I know the steering and framerails are setup the same way on grands. Don't know if a TJ brace would work because TJs aren't uniframe.