I`m using a divided deep on the bottom course with a screwed in division board that could be removed with entrances on opposite sides.I would consider putting openings at opposite ends. I put them side by side and had no problems but it seems like looking for trouble.
I use just an ordinary bottom with a strip of 1 1/2" wide material nailed in the bottom from rear to front of landing board. That is wide enough for the inner walls of the 4 frame boxes to sit on. In my case I used a standard deep hive body with a 1 1/2" thick divider in it for the first course of double 4 frame nucs. You can see where the screws go through to hold it, or removed to revert to a regular deep hive body.
I did not allow them to cap that honey super above the excluder but they were on their way to do it.