There is a modern design of old technologie available, these casings are best industry practice.
Overall containing a dozen huge FPGA (not ASIC!) chips, 6 on a single Hash board.
Just from my (outdated) experience running ZTEX boards, those who closely assembled a Cairnsmore1 device:
They did not last for long, old devices usually featured 3 of 4 chips remaining and 1 dead chip which was not replaceable. Placing 6 on each Hash board requires perfect cooling conditions.