What are the rules for re-entering Thailand on a METV before its expiry date?

Guys, I have a few questions regarding METV in this example scenario:

Say, I have come towards the end of the 6 months validity of the METV visa. I leave Thailand by air, say, 5 days before the METV expiry date (the "Valid Until" date). Then I re-enter Thailand by air, say, 1 day before the METV expiry date.

1) My question is if on re-entry I will get a stamp for additional 60 days in the country, which by definition will bring my total stay beyond the 6 months validity of the METV visa (i.e. beyond the "Valid Until" date).

2) Can I get a 30-days extension on top of these 60 days, while in the country?

3) Have you done this or do you know anyone who has done this, so that we have evidence that it works?

Thanks in advance!