Not obvious, is it Joe? OK, I don't know
; but, seeing as no-one else has come up with a definite answer, let's 'Play Detective' a bit ...
1. It's a Nippon Denso unit. Now those first appeared (I believe) on the 350/500 GTV (and then later on the 350/500 Sport Desmo). But in the photos I've found, they all look blue-faced, e.g.
2. Similar but different N-D instruments were also used on the Darmah. But it's not a standard Darmah unit - they too were blue-faced
3. Ditto, to the best of my knowledge, all MHRs, MIlles and S2s. But I could be wrong here - if I am, some one will swiftly correct me, I'm sure
Hmmm. Ok ...
4. It's got the Giugiaro typeface. So it can't be any later than the F1 and its variants.
5. I think all the Pantahs, up to and including the TL, used the by-now-familiar, blue-faced N-D instruments. Here's Phil Ainsley's close up of a 650SL, for example:
And here a 600SL:
And similar for a 350 TL.
Ok, so no good. But let's Keep on Truckin' ...
6. The 1985 F1 also used N-D instruments. But, again, in the photos I've seen they're blue-faced (e.g page 50, Ian Falloon's "Belt-drive two-valve twins
7. Now, the 1986 F1 DID
have white-faced instruments. But I'm pretty sure they were all Veglia units
. And according to Ian F., the same went for the F3.
8. So I wondered about the F4 ? (Edit: Woops .. I mean the 400 F3, of course
). Used Nippon Denso, according to Ian; but he doesn't say if they were blue or white-faced.
9. Or how about the Montjuic/Laguna Seca/Santamonica F1 variants? White-faced instruments, but I don't know whose; but why would Ducati NOT have used Veglias, as on the regular F1?
10. Otherwise, it must have been destined for a Utah or Rollah ...
All the above doesn't answer your question, I know
. But it might spur someone else on to have a go!