I have added and changed some parts of the truck’s electrical system. The biggest change is the addition of a Crimestopper alarm/remote starter. This module replaced the factory remote keyless entry system. It works from a good distance away, Crimestopper claims 1500 feet, and protects the vehicle with a shock sensor, door switches, hood switch, etc. I hooked it up to the horn to avoid using the cheesy 6-tone siren that came with the unit. I have also upgraded the battery cables in the truck to support the increased loads that the stereo system draws. I rewired the headlight system to allow all 4 headlights to be active when the high beams are on, and to supply more electricity to the lamps. I recently added an Optima Yellow Top deep cycle battery to run my sound system when the engine is off for a long time.