"well grab yourself a multimeter and give it a test then. you can see the pinouts here"

I did just that - I installed the 7 pin harness on the back end, tested with a multi meter. Found not all the lights worked (don't recall exactly which ones.) Then after I installed the relay/harness thingy up front everything worked.

My "philosophy" (for what it's worth) is that you got a $20 something grand truck. Don't cut corners and blow off the $55 harness - do it once, do it right!