What kind of damage can be done and what needs to be repaired if a 3800 series II is ran after gas gets in the oil and wont stay running anymore?
Depends on how gas got in the oil. Did it show up in the oil or was it accidentally put in?
I believe it got flooded and was turned over for 10-15 seconds at a time for a few minutes
Very little gas would have mixed with the oil that way. If that is the case an oil change, without driving the car, would probably be adequate.
It could be a blown head gasket
Remove the vacuum hose from the fuel pressure regulator.
If gas leaks out of this connection, gas is being sucked into the engine and contaminating the oil. And that’s probably why the engine won’t start.
After repairing the leak, replace the oil and filter.