I'm a sucker for stock YJs....would love to have one someday....anyway, good looking Jeep for an '88. Profile should be pretty easy to fill out, most likely the carbureted AMC 258 I-6, Dana 30 front axle, Dana 35 rear axle. NP231 transfer case, and being that it is an 88 I'd guess you have the Peugeot transmission. 3.54 or 3.73 axle gear ratio but I'm only guessing here.
1984 CJ-7 Renegade
2005 TJ X (daily driver)