stellar rs1050 2004 chevy silverado

Good find, Mr. Smoke!!! 

As for the bypass module, if you want very reliable and real easy, look for an iDatalink ADS TBSL PL bypass module.  They can be found for under $40.  Here is a link to the install guide  :  http://cdncontent2.idatalink.com/corporate/Content/Manuals/TB-PL/ADS-TBSL-PL_20110120.pdf   Type 6 is the correct diagram for your 2004 Silverado.

For vehicle wiring, here are some sources :

Here is a link to Bulldog Security :  http://www.bulldogsecurity.com/bdnew/vehiclewiringdiagrams.asp

Here is a link to Ready Remote :  http://www.readyremote.com/main.asp

Here is a link to AudioVox :  http://techservices.audiovox.com/AccessRequest.aspx    Sign-up & info is free.

Might need a relay or two for the install.   I'm sure you realize that this RS1050 is an "Add-On" type remote start system and looks for 3 (-) Pulses to initiate a remote start-up.   If you use the Factory FOB's and a Lock command to do this, you are using 8 year old, short range, transmitters.  IMHO, it would be worth the $50 to get something like an Avital 4113 or 4103 system.  More reliable, more features and much better range.