Not necessarily. I have a 2WD 1988 MJ and love it. I thought about converting it to 4WD and acquired the basic parts needed to do it (4WD transmission, driveshafts, transfer case and shifter, console, front and rear axles with matching ratios and new weld on spring perches for the rear axle). I realized though that with three 4WD Jeeps (TJ, LJ & XJ) and I didn't need another one. It's a blast to drive and quite different compared to the others, light on its feet so to speak. I'm glad that I kept it stock.
That's a nice looking MJ. The ad says that it has the original paint but that's not a colour I've seen. It might be Colorado Red and just a "funny" picture. There are a lot of different models but generally (not always) if it has a colour matched grill it's an Eliminator. If it is he's removed the original decals. The bumpers and fender flares would also be body colour. The badges have been "blackened" and the glass is heavily tinted. As good as it looks it can't be much fun to drive ... no gear shift knob. btw - the grill is on upside down.