I installed one on my buddy's 06-LTZ - The directions they send are very good. Just take your time and match up the wire colors as per the instructions. I was able to snip off some of the excess wire so that putting everything back in the factory harness was a bit easier. When finished, you couldn't tell anything had been changed. Like they said, make sure you solder the connections. Some nice black wire ties will come in handy for the prodject. Start to finish it took me about 2 hours, but I am very fussy and check everything 2 or 3 times before making a move.
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HAD - 94 Chevy Dually 4x4 - 6.5 Turbo
96 Chevy Ext.cab 4x4 - 6.5 Turbo
99 GMC Dually 4x4 - 6.5 Turbo
HAVE - 2005 GMC Sierra crew/6'box - 4X4 - Duramax w/Allison. Fully loaded - AiRaid intake - 4" Pinnicle Performance Exhaust (No Converter - Straight through muffler) - EGR blocker plate - Edge Juice w/attitude - 2" plug in Turbo Resinator -