I did this within a month of buying my XJ because the stock piece was leaking and didn't have a single problem. I ordered a CSF 3 core, all metal radiator from DPG offroad for around $170 shipped.
I had a haynes manual handy but it really didn't help me too much. Search this forum and NAXJA for a write-up, they are definitely out there.
Basically, drain the coolant from the petcock on the passenger side of the radiator (mine was behind the turn signal under the headlight, hard as hell to get to). I just took a hose off and drained it that way. Unbolt the core support and take it out. It'll probably give you more room to take out the battery too. Take out the electric fan as well as the engine driven fan shroud. Take all the hoses and lines off. You need a fuel line tool to get the transmission line connector off. Mine took forever to me to get off. Pull the radiator straight out and reverse everything. Took me an afternoon plus a trip to autozone to the the fuel line disconnect tools.
Much more satisfying doing it myself. I've never taken my Mustang to a shop for work, I don't plan on taking my Jeep anywhere either (except maybe for the gears, but I had a friend help me do them in my driveway on the stang).