Thanks for repies. PC it is the vertical piece (toe kick) Will follow Larry's instructions. Was planning that way but thought better to get some input to problem than just cut away.
The toe kick is cosmetic and doesn't support anything. Cabinets rest on their sides only. Support for the back comes from their attachment to the wall. So, if it's just the toe kick that is rotted, just replace it and fear not.
Now if the cabinet sides are rotting too, that's a bigger issue. I'm not a fan of the traditional method of resting a cabinet on shims on the floor because one potential problem is that the sides can wick up water that gets under them, leading to this sort of failure. In a new install, I'd use steel leveling feet, but they require drilling from above for access to the adjustment screw (and eventually plugging these holes), plus you cannot install them via the toe kick space. However, you do still have the option to use EZ-Levelers. With the toe kick off, you can slide these in, lift them until the touch, install the screws into the cabinet sides and then tighten them to take up the weight.
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