The remote starter kill wires will go in-line with the factory starter wire, it will be in the ignition harness just behind the key assembly. Using a test light (that doesn't feed back ground) look for a heavy guage wire(bigger than most, but not always). Get to where you can access the harness with ease then after inserting the test light in the first wire, crank the starter over(just a bump/real quick). Continue this process till you find the wire that only shows "power/positive" during "starter crank" but not any other time(example when the ignition is on but the car is not running). Once you find this wire using a pair of side cutters, cut the wire (don't cut it to close to a harness) as if you need to re-connect it you'll be up a creek.
Side NOTE: some newer autos have more than one wire that shows power during crank, I think you shouldn't have this problem.
LEE should chime in soon (if he's not raising hell over the holiday) to give the the wire codes to look for (like starter wire is white with a red strip, constant is solid red, etc) so wait till he does so..
Usually to access the ignition harness I will drop the finish panel on the drivers side of the lower dash board (usually it is only a few screws, some may be hidden on you). On the alarm side of the starter disable, it should have two wires that go to the dash board starter wire. One will be for the "hot" while cranking(cause if the wire is now cut only one will show power under cranking condition). The other wire from the remote start will go toward the other side of the cut wire, under the dashboard(we call it the starter side) easy to see why cause if you put power to the now cut wire that is away from the ignition/cold during crank it will try to start the truck.
For the delayed doom light, once you get the wire specs/color using a test light you can look in the driver left side kick panel. This is the finish panel to the left of the brake pedal where the upholstery meets the rug. This wire will show either ground or power while the doom light is on, it may also show the opposite when the doom light is NOT on.
It has been a while for me to do the doom light delay so I'll leave it up to LEE to further help you, feel free to ask more questions as I'm sure there may be more info that you will need. If you are confused re-read what I have written, a few times slowly this may better help you to understand the book of info I have given you.
PS: Here is a link to an install to gie you the general ideal of where and what to look for, though it is not the same as your truck. It does show the HUSH panel removal, and the left side kick panel removal as well.
http://www.autotoys.com/New_Tech/DIY_98/ph42/ph42.htm