Just picked up a late spec Vox Clubman Bass

All original electronics & fittings. Tobacco Sunburst with a healthy dose of lacquer checking.
Most mornings I drop my wife off to work by our high street guitar shop. A few days ago I noticed the Vox Bass sitting in the window & had to have it. The guitar shop's landlord discovered the Bass sitting behind the chimmney stack in his attic about 10 years ago when he'd lived at that house for over 30 years. It's likely the Bass was there for around 40 years!
Serial No: 67203 (1966?)...stamped by the "A" string Tuner. Looks to be a solid dark-stained Sycamore fretboard. No Date Stamp on the Neck but has a round ink stamp in the Neck Pocket that reads "7" + "B" & "G" (letter "F" punched into the wood just to the right of the ink stamp?). Pot Codes JK. Strings are old but don't know what vintage yet...they're roundwounds that now sound like flats

The guitar plays suprisingly well. Action & intonation are fine. And it sounds good without plugging it in yet.
Such a cool piece!
Can anyone shed light on the Neck Pocket info?
Confirm the likely date of production?
And did G-plan make the mahogany Bodies aswell as the sycamore Necks?