I've always wondered, but have not a chance to research, does anybody know what pitch means? i.e. 9mm pitch and 10.5mm pitch. I found in the FSM the pitch of the first gen and 2nd Gen Boxes are 10.5.
Now getting back to the steering stop. I have not tried this yet, and at some point I do want to try it because I have a very tight non "A" box sitting around. But I believe if you have the bushings for the external stops, the box will work.
These pictures don't have the bushings, but you would add them to the triangle piece on the crossmember...
And to the casted tab (where the hole is) on the idler arm and pitman arm. Idler arm shown.
EDIT:
Found pictures of a steering box with what looks like an adjustment screw instead of a bushing. The FSM calls them "stop lugs".
At this point, I don't know the part numbers for these external stops.
.