I installed my WH TB riser before I had the body on, sans engine, etc. I put my whole front end suspension together as best I could, and then looked at where the different suspension components were in relation to one another.
I first used ratchet straps to cinch down my axles to the approximate axle to frame height that Paul recommended for my WH 3.5" SL. If you know what springs you are using, call the vendor and find out where the frame rides respective to the axle when used with those springs.
I next looked at the geometry of the different bars, specifically keeping the drag link as parallel as possible to the track bar, and keeping them as close to the same length as well. This will let those tubes go thru their respective arcs of motion in the same range of arc, if that makes sense.
This will allow you to put the TB riser where it needs to be, and the bolt should be mounted in the same vertical plane as the original bolt was, so that the lower end of the track bar does not move forward or backward in its position relative to the axle before it is welded in place. This keeps the axle in the same position while your suspension compresses and extends thru its range of motion.
Check out my pictures, I had to deal with my project going TRO, machining my own knuckles for High Steer Arms, and adding a RAM assist to the tie rod. But the geometry should be similar on yours at the end. THe last pic shows my mock up with a TB drop kit and the 3rd pic shows my final result. I did not have the suspension compressed enough in the beginning, and I found later I did not need the TB drop kit for my 3.5" SL. But look how parallel the TB and drag link are. That is what you want to mimic. Mine will be different from yours because of I have a inside the frame PS box that is really long, and I had to bend my Pitman arm (might need a bit more angle, but its getting there).
I hope this helps, and thank you for serving our country.
