Widening cabinets to fit a OTR microwave
Picture(s) would help for your "move these cabinets over" statement. But, if you have room then it's just unscrew from each other &amp; from studs...in that order. To then re-mount them to other studs &amp; back to each other.

However, you may also be able to swap cabinets to get a few more inches. If you have cabinets on other walls there may be a thinner one in an area that can accept the fatter one.