Well son of a...
So - drove to work this morning - about 30 mi. Car ran fine. No fluid smell as I had always noticed before when it leaked.
Left work in the afternoon, 95 degrees, stop and go traffic for 15 min. Turned off.
After stopping for 15 min made another 15 min stop and go drive before hitting the hwy at 70-75. 10 min into the hwy trip --- **** --- heavy smoke in the rearview.

I got it off the road quickly, so I hope any chance of damage was minimized.
Trans fluid was puking everywhere.
I wonder if I did something wrong when I re-routed the trans lines.
The heaviest area of wetness appeared to be toward the front of the engine compartment toward the passenger's side so i was thinking it may be leaking at the inlet inlet of the stock tube cooler, but that connection looked dry.
I abandoned the trans lines into the radiator. Do those need to be capped?
I ran from the top connection at the trans to the passenger's side of the tube cooler, out the tube cooler to the aux cooler, out the aux cooler back to the bottom connection of the trans.
I would like to find a ruptured hose where it runs around the radiator to the pass side of the tube cooler, but that would be too easy (besides, why would new hose rupture?)
I won't have a chance to look close until tomorrow. Just looking for some ideas on likely causes.