How long do I need to stay out of Thailand before re-entering for a tourist visa after an overstay?

I think we've taken this thread as far as we can constructively take it

There is no one on this group who can say with certainty how it will go for the O/P at the border when they go to stamp in.

All they can do is be prepared, and hope for the best (y)

We wish the O/P safe travels, we are done... ,,,

You can make an appointment at the Thai consulate and get a tourist visa to be safe.

Doubtful you had a real tourist visa (that you bought from a thai consulate in another country before you came here) 😮

and

it's much more likely you just showed up here and were stamped in free for 60 days on the visa exempt entry program. <- which is not a tourist visa, not even a visa at all, just a free entry stamp for 60 days

There is no official amount of time you have to be out of the country before you can attempt to re-enter and get a new 60 day visa exempt entry. However if they think you're living here on free stamps they can question you on entry, ask for proof of funds, proof of onward travel (back to your country in 60 days) and proof of lodging.

All you can do is try to re-enter and see if you get in or not