How big of a lift can you go without having to major modifications to a 94 zj 318. I put some 1 3/4 polly spacers on last year, but would like to redo the whole suspension system now. Any recommendations?

I'm about to lift mine 2" with spacers...check out www.jeepzj.com they have them lifted up to 3"

up to 3" without any driveshaft problems? or any such problems?