LS SWAPS: Wiring Harness and Wiring Guide Mar 10, 2015LS SWAPS: Wiring Harness and Wiring Guide. March 10, 2015 by LS Engine DiY. The wiring aspect of any LS swap is undoubtedly the most difficult. 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 Amazon: 5.3 wiring harness Mophorn Standalone Swap Wiring Harness for 03-07 Chevy GMC Cadillac Vortec 4L60E Standalone Swap Wiring Harness DBW 4.8 5.3 6.0 EV6 LS1. 4.3 out of 5 stars 4. $409 $ 409. 99. FREE Shipping by Amazon. Only 1 left in stock - order soon.