LS SWAPS: Wiring Harness and Wiring Guide - LS Engine DIY Mar 10, 2015LS SWAPS: Wiring Harness and Wiring Guide. Most builders are familiar with fabrication techniques, trouble shooting, and parts swapping to make things work, but electronics rise to a much higher level of complexity. Wiring has carried an aura of mystery that can send a shiver down the spine of even the most seasoned builder,..Author: LS Engine Diy Custom Wiring Harness Build - GM High-Tech Performance wwwrchevy››How To›Engines & DrivetrainJan 16, 2014So for that, we knew we had the right guy for the job. We were able to snap a cheap wiring harness, from a LS truck engine and combine it with a few off the shelf parts. You'll be able to build yourself a custom sized wiring harness for under a $100. To be fair, this project will require a decent amount of free time.