The very early NS Bluesbirds did feature pull-switches on the pickup tone controls that split each humbucker independently. I reviewed one, in Iced Tea, for Guitarist magazine here in the UK and observed, “the coil-splits were a surprise – they’re not mentioned on Guild’s info page – and voice the slug single coils.” A second, in Antique Burst, was loaned to me to carry out pickup and hardware swaps for a column I write on the culture of modding.
Typically, I investigate the insides of review guitars but for whatever reason, probably a fast approcaching deadline, I didn’t. However, on that second Bluesbird, one of its first mods was a pickup swap; that’s when I noticed the bridge pickup wasn’t a SD JB but a SH-16 59/Custom hybrid. It uses the screw coil from a 59 and the slug coil from the higher output Custom (with a measured DC resistance of 7k ohms) and it’s that one that’s voiced with a standard split.
I did ask Naomi Con at Cordoba/Guild whether anyone could shed any light on the off-spec features but didn’t get very far. “We had a few issues come up with the first run of these including the coil split that you mentioned before (that feature is not spec) so maybe this guitar was part of that first run”.
Great forum! Keep up all the informative work.