Mudding Tight Corners

We have 3/4" aluminum channels to hold the rope lights inside our cabinets. We should have cut these off flush with the floor of the cabinet, but for some reason,the floor got cut out to fit around the aluminum channels instead. This leaves a gap, a "black hole" I don't want stuff falling into. I needed a very narrow offset spatula to mud the hole in, so my talented carpenter/subcontractor/tool-and-die-maker/spouse created this one for me.




Here you can see, top to bottom: 1) the gap left by the aluminum channel, 2) using the tool to pack in and level off the mud, and 3) the finished result (before sanding).

We're sort of designing things as we go along, which is not the best way of doing it. I think if I had it to do over, the rope lights and aluminum channels would only have come as far down as the open display shelves. I don't even remember why we chose to have them extend into the storage below, unless maybe it was to make it easier to rummage about in the storage section to find things.

Anyway, I've abandoned the idea of adding similar built-ins to the rest of the house. It's too time-consuming. I've lived long enough in a construction zone, and now, I just want it finished!