Ya sorry I will post the full story now that the issue has been solved.
Started off plugging in the harness and thought everything was good until I went to plug in the leads to the battery, the battery started sparking a lot and we figured out there was an issue. Went to check all of my connections and I had accidentally bolted the large positive wire as well as the fuse box positive wire the crankcase ground. Fixed that issue and went to turn on the car, got power but then the anti-theft system started locking me out. Tried key reprogramming but nothing was working so I went to the chevy dealer and bought a new key. That key worked and the anti-theft system disengaged. After that I tried turning the car on with lots of relay clicking and the dash flickering, went on for about 2 weeks trying to find the issue, went through a lot of different tests and found that a couple of wires in the bcm weren't getting positive voltage and we traced that back to the run/crank relay. That relay was getting power and I thought the fuse wasn't but it turned out I was using the multimeter wrong and the IP/IGN fuse was getting power. Dale E then mentioned all of the major positives and grounds to make sure I had all of those. I realized I was missing my engine to frame ground which in hindsight was not the most intelligent thing I have done, the wire was sitting on the shelf for a while and I had looked at it but for some reason wrote it off as not important. Once that was installed engine fired right up!
Just want to say thank you to everyone that was involved in helping me get through this! Happy Thanksgiving!