With a bunch of help I have the labs in a nearly-complete state.
Really bad monitors in Lab B have been swapped for the CASStoffs and I've cached 8 or 9 for later replacement when the remaining KDS monitors go. The remaining KDS monitors look OK right now, but as they get IDed as flaky I'll swap them.
Most keyboard/mouse combos have been replaced too, though there are a handful left which I'll do as time permits.
I've received one of the new machines, without a drive - which I expected (I have a bunch of spares) - but without a second IDE channel to plug it in to - which I did not expect. I'll need to find an extra-long IDE cable and plug both optical and HD drives in to the same channel (master-slave the two). Otherwise I'll have to buy two SATA drives. I realize that SATA is preferable in terms of performance and long-term reliability but I have all those extra drives...