I replaced my front lines with '95 YJ fronts, and the rear with a '95 YJ rear - I'm at 4.5" of lift. The OEM rear line was stretched like a guitar string and limiting droop. The front OEM lines, even with straightening of the hardlines and re-attachment lower down, were also acting like limiting straps. It's amazing how strong the OEM lines are 'cause I flexed up regularly with them for a good 6 months and they never failed (I had tested their "tautness" when the suspension & LCA's were new, and they were just taut, so thought I was OK - once the rear leafs broke in & the bushings wore a little in the LCA's and trackbar, things got beyond "just taut" both rear and front).
For the front lines you'll find that you may have to bend the lower hard line a touch for clearance at full steering lock - nothing much; just be aware and test to see what need be done.