I have 4.56 gears and Teralow 4:1 like Black YJ...
It gives me about a 73:1 crawling ratio on first gear.... It's good enough for what I'm doing.
I run 37" tires on that set up. ...
I like the Teralow system. I added 2 low when me and a buddy were building it.
It's a little slow for winter wheeing though