When i had a YJ/CJ i used a 2.5" J20 steering box, it worked fine with my 38" and 1ton, axle. NO assist.....
The biggest part is know how far, or how much, the tires are set back.
For me i had a 4" back spacing (8" wide rim)
So, what i'm saying is, your probable fine with whatever you like for links for the TRE.
Just watch the setback on your wheels, and let her roll..............
Now i have 35" tires and a 2" astro steering box, and it totaly fine, but......
If your a slow poke and like to turn the wheel back and forth (lock/lock) while driving a foot.
OR
have a 3" spacer on each wheel then with your 35" tires
disregard the above,
maybe you need an assist.....