Dude, it's like a 2 minute job. Unplug the wiring harness, unscrew a clamp, unbolt the box, remove old MAF, insert new MAF and repeat in reverse.
Don't worry about getting dust or anything in it, I put a cone filter on mine with an adapter I got off of ebay, and I had to use wd-40 (only thing I had within grabbing distance) to coax a rubber section on to clamp the filter, and I know dust, plastic shavings, and wd-40 got in it, and I think I might have even sneezed in it. I just lightly shook it out and My truck runs great. The cone filter is pimp, too.
Nevermind, you have a 99. I have a 91. Probably a bit different.