Re: thinkin about a 6" lift insted of a 4" go big or go home or to much to work
A 4" YJ lift requires either a 1" transfer case lowering kit or a SYE install and new rear driveshaft. The 6" kit will likely require the SYE kit which is the more expensive and labor intensive route.
The 6" kit will require more steering modifications.
If its 6" you want, consider converting to SOA (spring over axle). It's not always cheaper but, when done properly, generally performance better than a SUA lift.