10si alternator

[Awann99]

I'm having some electrical issues with my truck 72 k2500 350 4 speed.
Left my lights on a few days ago . Battery was dead the next morning. Swapped a new battery. Alternator was reading in the low 14s. Got to work and the truck was dead when I got out. Got a jump and to the parts store. All they had in stock closest to my year was a 1980 Camaro alternator. 10si internally regulated. Swapped the wiring over and headed out. Charging at 13.5 and slowly climbing. Battery was at 11.23 this morning. Any ideas and how to track this down. It's slowly draining when off.

My alternator wiring harness also did not have a ground wire.

To change the wiring I ran the blue wiring to the number one spot on the alternator. Rant the number 2 spot to the battery stud. Tan the red wire to the battery stud. The white wire on the original harness is snipped and I ran a jumper from the brown to blue write on the old regulator plug. Did I miss something?