Good point about casework on a project after something like a MiniMax which is the only amp I know of that has custom casework already available and matched prefectly to just this amp. On basically any other project, you're drilling your own panels for input/output/power/switches/etc, attaching the PCB to the chassis, doing power wiring, mounting the transformer, etc. For most solid-state, this is standard, with tubes you have the added options of how to mount the PCB (build on "bottom" of the board and mount PCB on or lifted to the roof with flush tube socket, air-wire tube sockets or have tube on PCB bottom-mounted with only a bit of the tube sticking out of the chassis - if at all).
For every project I've done, casework has generally been the most time-consuming task.