It gets all the way through the MPU boot, through the playfield reset, coins up, starts a game with playfield setup, then BOOM locks up/tilts. Tilt mech all looks decent. I'm in the end stages of shopping this game out and it did play fully until very recently. I did pull the MPU to put in an anyPin NVRAM module but that's not in there now. I pulled it back out when the game started acting weird and put the 5101 in there. I'm wondering if I should pull the MPU again and reflow all the headers.

The video shows the whole sequence from power up to locking up:

I'll check that and shore it up if it's low. Good place to start. Thanks!

It was the horizontal tilt switch under the playfield that was shorted. Must have gotten bent somehow during the playfield cleaning. Could have sworn I checked that but hey you were right. Thanks!