older alarm compat with 2005 chevy 2500

Just got a 2005 Chevy Silverado 2500 Duramax diesel as a work truck.. Not really interested in remote start at the moment, just remote door locking/unlocking. I've got two older Viper (DEI) alarms sitting at my house, was wondering what all would be involved getting one of these installed in the truck. I looked at the wiring guide for the 2006 2500 diesel, and it appears that there's a lot of extra modules needed? Do I really need these for the 2005, or is there something I can make? The two alarms I have in the drawer are a Viper 500+, (I could use a wiring diagram for this) and another (older ) DEI unknown model - FCC ID: H5LAL9144, S/N 002551100047 -06

The 2003-2006 fullsize trucks are all pretty much the same, so yes, whatever you read about a 2006 would apply to your 2005. There are some diagrams around (maybe online, not sure) about how you can run wires into each of the two front doors, wire two relays in each door, and also run two more wires under the back seat to control the rear doors......way more work than it's worth. Your truck doesn't by chance have manual windows, does it? I've heard there were a few with manual windows, but power locks, and those had regular plain doorlock wires available inside the cab.