The moment of truth - got in a rear panel for a super dense amplifier project, which houses two front ends that wires up to different output stages. Hopefully I will have time tomorrow to get the output stage bolted onto the heat sink to see if everything fits. It will be very close! Missing a few M3 screws and the switches, but those will be ordered next part run, but more or less everything is installed! Edit: not quite - there are pluggable buffers in front of the transformers that would block view of the relay - I need to add those in. Hopefully an update tomorrow when all fits!