How to raise the rear frame and eliminate your butt crack

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And it if works on the back, would it also work on the front?
Cut Here:
View attachment 273470

Create this gap to fill:
View attachment 273471

No actual math or testing went into determining the size of the gaps that would be created and need to be filled in my pictures, just guestimates that might be way off.

As I said, I am sure there is a good reason not to do it this way, but it seems easier.
Regarding the front, I looked into this quite a bit. You'll need an XJ pitman arm to retain the steering geometry. If you have or want to have a PSC steering box, then the radiator needs to be raised up.

After that, the front frame has far more bends in all directions making it harder to simply cut and raise like the rear can be. It's "easier" to improve the front approach by moving the axle forward until the track bar and drag link are nearly touching. Keep reading my thread and you'll see what I mean by easy. It isn't easy.