For those that have been looking for a how-to on this re:the 4.2L 6.
The starter is easily visible from the top. It's on the drivers side down low near the firewall. You can clearly see the electric connections on the solenoid.
1- Disconnect the battery Neg terminal (duh)
2- Disconnect the two leads that go to the solenoid. One is a 13mm nut for the main line and the other is an 8mm nut for the smaller wire (the other 13mm nug/line just goes to the starter body so leave it alone).
3- You can easily see the one bolt that holds the starter on, it's a 15mm bolt. Remove it.
4- Only one thing left and it's the only part that's difficult. The other side of the starter is not a bolt but a nut on a stud. It's also 15mm but you can't really see it. If you finaggle the loom that rests on top of the solenoid you can catch a glimpse of the nut with a flashlight(assuming you have your head cocked at the right angle
Anyway, with a 6" extension on a 3/8 ratchet and 15mm short socket you can do it by feel but it's a pain. If you slide the socket along the "valley" between the back side of the solenoid and the starter body it's maybe an inch above that straight up. I was able to wedge a small pen flashlight in a unique spot that held the aforementioned loom slightly aside so I could see the nut (barely) while I guided the socket onto the nut. I was in a strange contorted pose to pull this off but it worked, a helper probably would have made pretty quick work of it...I was not in possession of a helper.
5- Once that nut is off the starter actually comes right out the top, you just have to guide it past some flexible vacuum hoses near the brake booster and whatnot but it comes right out.
Installing the new one (I got a one at a scrapyard for $34) is simple other than the same nut that was a bastard to get off. Make sure you glue or otherwise secure the nut in the socket as you guide it back there (I wedged a bit of shop rag next to the nut in the socket and that worked fine). If you drop it back there you'll likely have to pull the starter back out to find it.
I did this in the parking lot of a grocery store in about 50 mins, it's an easy job other than that bastard nut.
Again, this is for the 6cyl, not the 8 which I understand is a sumbitch. Hope this helps.