Nick,
It's pretty straight-forward. Jack up the right-front tire, remove the tire, then remove the wheel-well liner. This will give you the best access to the turbo. Disconnect both negative battery cables (this will become important later, so do it first).
Remove the V clamp holding the exhaust to the elbow, then remove the oil return line from the turbo. From up top, disconnect the intake and discharge tubes, and remove the oil supply line.
From underneath the truck, remove the two turbo mounting nuts from the inboard side of the turbo (a 15mm deep socket and long extension will get it done). From up top, or through the wheel well, remove the other two 15mm retaining nuts, and the turbo will come free.
Remove the manifold heat shield, then start removing the 12 manifold bolts, noting which locations get studs, and which get just hex-head bolts.
The tricky part will be the heater hose bracket on the back of the manifold. You need to pull it off the mounting stud, and it's not exactly easy to do. Remove some of the adjacent hold-down bolts on the hard line to allow the line to flex a little. With a pair of Vise Grips on the bracket, and a screwdriver/prybar behind it to help, it can be pulled off the mounting stud (working through the wheel well). Some guys get frustrated and just cut the bracket with a Sawzall, then tie-wrap it to the trans dipstick when they're done. To each his own...
Once the manifold is off, use it as a template to assemble the ATS manifold. Put the male part of the manifold in the freezer, and the female part in the over at 350°. Take them out, put a little anti-sieze on the joint, and assemble. With the difference in temperatures, it should slip together easily. Get it aligned properly, and install it back on the truck. I used new gaskets when I did mine, but you can probably re-use the old ones.
If I remember correctly, you have to remove the studs from the old manifold and install them in the new one. Either use a stud remover, or just use two nuts from the turbo to remove the stud (jam the nuts together on the stud TIGHT, then turn the lower nut counter-clockwise to remove the stud. Use the same technique to install)
Get a couple of bolts started on both sections of the manifold, to be sure you have the alignment correct. Re-install the rest of the bolts, wrestle the heater bracket back over the mounting stud (if you didn't give up and cut it in two), and torque the bolts to spec. Bolt the turbo back into place (make sure to get the gasket back in place, as well), torque the nuts in place, put the oil lines back on, re-attach the exhaust to the elbow, tighten up the clamp, re-install the intake and discharge tubes, and you're done.
Good luck
-Tom
Attention: TDR Forum Junkies 
. Id like to install the manifold myself. What do i have to look for and be careful about. I know i need to remove the turbo... . how dangerous can this be. . Can anyone give me some pointers/help on this. 
