I would try the wiring myself but since it's my daily I would like the piece of mind that I did it right so maybe the premade harness is for me. I'll definitely be buying a bigger aluminum radiator for this upgrade along side the factory 06 fans.

 

Great, Great info! Thanks for this! I feel that the best route for me to take is doing the Nelson premade harness since this is my daily driver at the moment. Awesome info nonetheless!

 

the factory harness is like maybe 90% plug in play. if i remember correctly there are 2 wires that have to be pinned in to the PCM, so if you are uncomfortable with electrical then you might want some help. and as others stated, yes a tune is needed to make them work.