Yeah the 241 Rock Trak is the way to go, much better than to spend the $ on a 231 doing 4:1 and SYE. You can get one for around $1K slightly used. I got mine for $1,100 on ebay and sold my 231 with SYE on ebay for $500 so it was a nice $600 upgrade on my 91'.
I'll sell my 231 23 spline from my 98' XJ with 130K miles for a 242 23 spline straight up if anyone wants to. We both cover shipping. I had the 242 in a few of my XJ and ZJ and like it for it's full time 4 high mode. I can do this after the 1st of the year, I'm too busy before then with moving and going to Hawaii for a few weeks.
Troy