Take a good hard look at the general construction a a "RV" base cabinet..
You WILL end up having to cut up to the point of nearly destroying the integrity of the cabinets and then have to figure out just how to reinforce every single base cabinet.
You would be better off just completely ripping them out and building your own, would be easier, faster and cheaper..
Then you will have screw/nail holes that was used to hold the cabinets in place in the floor that you would have to fix, that would most likely begat a complete flooring replacement..
The flooring replacement then will begat another "project" and so on..
For the very little amount of time we spend standing at a RV kitchen cabinet, I find no earthly reason is needed for a toe kick.. The slight amount of "discomfort" does not make it worth it to me.
Unless you are "fulltiming" leave it be, don't open the can of worms.