Having just gone down the U-shaped furniture route (from van furniture), and owning a SWB T6, I have the overhanging bit over the step (even with a van -x narrow step) which I don't really mind. I managed to do a bit of trimming so was able to push the furniture back towards the rear doors about 3 inches or so, mainly so I can have more room to push the driver seat back a bit being a pretty tall chap.
I opted for the pull out drawer so have no real need for the opening side cupboard so to make it a bit more tidy I fashioned a bit of ply and some left over carpet to make a panel.......in my eyes it looks a lot better and gives a tidy finish covering up the ply edges and giving a bit of cushion support. pictures before and after below.
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