If you get a finished side, you can just get a 24" base cabinet door and stick it on later.
Screw it on with short screws from the inside.

Can you take a picture of the cab you are talking
about? I want to post some images for you but I fear
I am going to post the wrong images. I think I am confused,
which happens to me often. : )

I have not seen a clock on an end panel, but it is
a lovely idea and I think it could work. I have seen
some shelves and even tiny end panel storage that
might be interesting.

~boxerpups

I don't have the cab yet ;)
I'm thinking ahead in case I lose my mind during the demo.
Spose I better take notes.

I guess the real concern is whether the trim leaves enough flat space to mount the clock and corkboard. But I don't really have a door style yet.

If the cabinet is eighteen inches deep, would I be able to fit something inside the trim?

Here are a few end panel ideas but I am not sure if they
will help you. At least you can think about them and
plan your own kitchen.
~boxer