Conversions & Hybrids - harmonic balancer

ok this is an odd question. i have a 5.3 with the kwipperformance bracket setup. it looks like everything lines up pretty close but when i start it the belt stays in the right groves in every pulley except for the balancer pulley which jumps one groove inward which shreds the belt after a few minutes. my question is could my balancer be backing off? can someone measure how far away from the cover it should be? or give me some reference to find out if its backing off?

I think that due to what the belt is doing, the harmonic balancer is in fact backing off the crank snout. I would get a new crank bolt, go liberal with some loc-tite and run it back on with an impact.

Thanks I dug into it deeper today and found the lip of balancer is 3 11/16" away from the front cover and it was dead on. Found out it's the ps pump pulley.