I've done some poking around in those 'corner-columns' in my 5.0 for other reasons. Based on that and you being a woodworker IMO you'll have no problem with the mod you outline or even completely eliminating all below the 'overhead' cabinet.
TIP - Talk with your sales consultant about adding pieces of the paneling, trim, and even wall-covering (vinyl bonded to foam) that matches your chosen interior as 'loose / materials only items' on your build-sheet. I did that, I'm very glad to have the materials for mods, the cost was IMO very reasonable IF you have those materials packed in your trailer when it's delivered (no shipping cost, which is otherwise prohibitive for that sort of bulky stuff).
Have Fun!