Neighbor's bought a 2017 Spark LS from a long way away, woke up to a car carrier backing down the dead end
Got to advise them on what it needs, a RockAuto cart is being formed
I'm feeling a little better, my eBay shenanigans netted me 3 parts only/DOA Snap on MT2500s (the red brick)
My first Snap On tool

I'm up to 2 of 3 working
Some light soldering and cleaning, plus some fresh 9v batteries
The yes/no keys had buildup on the membranes, so they were either unresponsive or jammed on
They're the later v2.2 backlit models, that's a plus
The MTG2500 is still inop, I'll tear into it next
Cane with everything I needed, except a GM ALDL 12 pin adapter, keeping an eye on another auction
The cartridges reminded me of late 1900s video games, like the Sega Genesis

I bet
@dishdude would know all about such activities
If it's obscure OBD1, imma diagnose it