It is probably a lot similar to installing the remote starter I installed on my wife's 1997 Camry. There is a lot of hunting for the correct wires, getting to the wires, soldering wires together, tucking wires and such back away nicely, etc. If you want to get a feel for what you are dealing with, you can find the tutorial for it in the stickies at the top of this forum, or it can be found here:
http://www.tracystruesoaps.com/tutor...testarter.html
If you are patient, particular, and know how (or learn how in my case) to solder, it's not bad at all. HTH