This is fascinating stuff, Geoff, and very relevant to my own interests!
I've been lucky enough to find a copy of the Palmer book on Abebooks at only £50 inc postage, so am looking forward to reading that when it comes too.
So hurdy gurdies may have been played by, or perhaps for, the gentry - now that's good news!
I wonder, is it possible "Clarycord" may be a misreading/variant of clavichord? I'm not a great scholar of this, but from what I know, I quite agree about the others being harpsichord types.
Of the others, sackbuts and trumpets seem to me the instruments of professional musicians, played for rather than by the posh lot.
As for the others - when medieval illustrations allegorise music they tend to have everything in sight from psaltery to harp to shawm and trumpet, often in the same array of angelic players. It's not thought likely that they'd have actually played this lot at the same time, but there they are. I wonder if this is a similar assembly? Again, you don't generally find harp and trumpet in the same setting in the 16thC.
I'm not trying to cast doubt on your smashing idea here, just chewing it over.
...And what's "Solacyous"? Like a Solar, or salacious?
I would love to see an image of the time showing a gurdy played by anyone of high status, or in a high status setting, rather than street beggars, or allegories of low life & morals.
I wait to read what follows here with great interest.
It may amuse you to know that I also asked the Northumbrian Smallpipes list about the tunes Old Sarah played... I know it's way OT on that group but there are some superb tune historians, and now they're happily discussing hurdy gurdies!