I'm hoping y'all can advise me on a rather arbitrary decision 😉

I've come across three motherboard combos and 3 different AT cases and I can't decide which board/CPU should live in which case! I have the following to combine:

1x IBM XT-style flip-top case (pictured)
1x full tower AT case
1x mid tower AT case

1x Pentium 166MMX + mobo
1x AMD K6-166 + mobo
1x AMD K6-2-266 + mobo

Thanks in advance!
James