Thanks for the extra added info, much appreciated.

Quote Originally Posted by AaronB31 View Post
- In my personal opinion, you should keep the truck harness in the truck and add the dsm harness to it. This is real easy, all you need to do is combine the battery terminals together and ground the harness in places it was originally grounded to the car. This saved me the trouble of making new wires for headlights, turn signals, etc. Taking the truck harness out will look much cleaner, but it's adding a decent amount of extra work so this is up to you.
About this part, yes this SHOULD be kept in the truck, it is NOT recommended to remove it and I did not say that in the original post. You should however remove the truck ENGINE harness, which is separate from the chassis harness(headlights, turn signals, etc.)