I have for a sale a used Klune V Underdrive unit. 2.7:1 ratio.
This unit has a 23 spline input and 23 spline output, with direct shift lever. Comes with mount and 1" spacer for to adapt to any jeep tranny.
If you have a 4:1 rocktrac this will give you 2.7:1, 4:1 and 11:1 crawl ranges. This is not a cut up NP231, this is a tried and true underdrive unit.
The unit is in good working condition, shifts smooth and has good clean internals
I bought this a few months back for $1,250. Will sell for $1000. Located in Fresno CA...Will ship for cost to ship.
The pictures below are from the guy I bought it from. It has since been cleaned up.