My philosophy is to always check the easy things last.
It was 1 of the tensioner wheels that hold the gantry ends snug against the rail had loosened up, letting that side of the gantry tslip and get out of alingment. It was a 5 minute fix once I realized what it was. Natrually I assumed it was the IR eyes since I'd adjusted them yestrday.
Gonna Locktite those as they seem to want to back off.
One thing about these i5000s, they're easy to work on and light weight enough to manhandle into position when needed.
Also kudos to Westech Supply - not too many dists who're reachable on the Sunday morning following Christmas.