[Festus2]

Your best bet is to ask the dealer's service/repair department for advice as to where the kitchen counter extension is usually mounted in your particular model. There may also be some other similar models sitting on the lot that have the extension already installed that you can go into and have a look.

I'd place the extension if at all possible in a location that, when extended, it will not block or interfere with passage from one part of the RV to another.

In case you should ask, Keystone does not have any electrical, plumbing or any other schematics that are available for owners.