MB and others, since you have to make so much of this equip yourself would it not be easy to make 2 supers to cover the length. I made several 6 frame nucs because the wood was already the right size. 10 frames with a little extra space(since this is a super) with the width of the 2 boards in the middle should work out to split the difference. Just a thought as I am thinking about using 2 1/2 supers on my langs because of weight. I may make some 8 frame boxes in medium size, but then again I worry that 3 medium 8 frames may be to small to get them thru winter.
Since I'm wanting a long hive anyway and all the same size is nice, I was thinking of some five frame Dadant Deep nucs or even four frame. But so far, I'll probably just put a regular medium super on instead.