This is what I made and has worked very well so far. My truck does have a Rancho 4" lift. I adjust the height by adding or subtracting washers. Still rides nice when sitting on A-arms.
X2, I bought one of Bens lockup box/ tap shifter combo's with the LED display and works great! He shipped it fast and answer my questions in a timely manner. Thought all we have been hearing is negative thing's, how about some positive experience's.:thumb:
A BT lockup box can also unlock your converter at anytime also! Which is what I was referring to. I had my TCM programmed to do 3rd gear starts and love it! I hated the 2-3 shift.
Do you have a lockup box? If you try 4th and it starts pulling the rpms down at the end of the track you can unlock your converter to keep the rpms up.
I'm happy with my grizzly also, but they do make a little noise when turning sharp. You could try and find a used locker out of a Dodge 11.5 also, they are supposed to be more durable than the G80.