Tom:
It figures…wive’s always want to rearrange the furniture.
Casters will raise the height of course so you will want to reduce and height related parts accordingly.
I would recommend installing them up inside the base frame
so just 1/2″ to 3/4″ of the caster shows.
I would also recommend using HEAVY DUTY casters as the L shaped bar will top a couple hundred pounds, plus all the stuff behind the bar.
Structurally, I think if you beef up the connection of the 2 sections, you should have no problem.
Send in a photo of this bar if you buid it with casters, it may be the first rollin’ bar!
Cheers!
Steve