No pro at this, but if it were my beer, I would put it all in the refrigerator to stop the yeast from making any more CO2 first. (will also prevent bottle bombs)
Then give it a few days and try one. If still too carbed try a long pour to release the excess CO2. It may take a while to pour a glass, but it could be the easy way out.
If not I'd think poping the caps and recaping would force some of the CO2 out of suspension and might get you where you want.