Well you could always stack 16 eight ohm speakers per channel, four rows side by side of four speakers stacked. Each stack of four run in series, and the four rows run in parallel, and that would keep you at a nice easy to drive eight ohm load. How it would sound is another matter, but it would go LOUD!
I visited Wade Burns' home once years ago. He was the chief electrical engineer for Dynaco at that time. He was using a Dyna 416 amp with four A35 speakers in a series parallel stack on each side of his fish aquarium. He played it blasting loud for me and the poor fish were terrorized!

Not my cuppa tea.
Frank VA
By the way, going to 4 ohm speakers just to get more power does not work. The four ohm speaker, all other things equal, takes twice as much current to drive as an identical 8 ohm speaker, and so the energy into the speaker remains the same, only the power amplifier runs hotter. The amplifier has to work harder to put out the same V into half the R.