1996 Roadmaster wagon shuts down

Bought a 96 roadmaster wagon advertised as runs great. Ive had wagons for over 20 years.   Test drive of him first then me felt a few things.  Did some work got plates and out of three times driving it it has shut down four times.   First time was pulling onto a busy highway in rush hour.  Serious stuff as i was coming on from a sideroad when it shut down with oncoming traffic.     Didnt realize it at first but the three days it shut down on me I had driven the car an hour or two before.  

Now have done videos of it over 11 days and three times each of those days.   I run it for half an hour or an hour shut it off.  Hour half later come back start and run it again and for sure it will fail. Shut off, or idle will surge and rev on its own and stall or just stall then be hard to impossible to restart or restart go for a bit and stall again then maybe impossible to restart. Its all on tape and many failures.   Then I would start it another hour and half later a second time and same thing repeated failures.  I likely have at last 50 failures and it is 100 percent repeatable that it will on this second time it is run.   Had the car been run on test drive, then sat for an hour and half and I drove it again it would have failed but who knows that other than the guy who has owned it for two years.   

Car is dangerous.  

Previous owner had it in to the shop and had some wiring drain short  fixed and then didnt drive it again and put it for sale right after that shop did the repair. In the notes with the car he replaced three starter motors in a short period of time say two months,  clearly he had been repeatedly starting this car or trying to over and over and toasted the starter motors.  One was replaced for free so really that shop got hoodwinked just like me.

Any thoughts appreciated