I would get under it and do a measurement from your axle to the top of the suspension mount. You may also look for clues such as name brands on shocks and suspension parts. As I recall, many of the lift kit manufacturers put their logos or model numbers on parts.
Denis A. Baldwin
1991 YJ 2.5L, 1" BD MML, Ultimate 8.8, Super D30, 4.88 Gears, Detroit Lockers, 36" Super Swamper SAM-26s on Ion 171s, RE SOA w/RE1445 springs, Bilstein 5150s, 3in. BL, custom cage, Warn M8000, Double D Dash/OHC, 4Low Front Stinger Bumper, DirtWorx Rear Bumper WTC, Tube Fenders, RR OTT Steering and PAID FOR.