I'm about to do mine too. Same flat black paintjob.
There was a sticky a few months ago about the best way to paint a Jeep. It gives a lot of tips that are pretty priceless. I know the best thing you can do is prep, prep, prep. Spend time masking everything off. Make sure your humidity and temp are good. Buy a cheap HLVP spray gun with an inline filter and a medium duty or better compressor. I'm using Summit Racing's flat hot rod black (2 part) that is, from what I've seen on other vehicles, a nice finish that holds up to abuse. I'm not going to put a shiny clear coat on it, just two coats and a finish coat of sealer.
Denis A. Baldwin
1991 YJ 99 Vortec 5.7L, SM465, NP205, 14 Bolt Rear, Dana 60 Front, 5.13 Gears, Detroit Lockers, 395/85R20 46" Michelin XML tires on 20" XD Wheels, Cherokee Offset Springs (10" front to back stretch total), Bilstein 5150s, 1in. BL, custom cage, Warn M8000, Double D Dash/OHC, 4Low Front Stinger Bumper, DirtWorx Rear Bumper WTC, Tube Fenders, Comp Cut, 1 Ton HD Kingpin High Steering and PAID FOR.