Grind 4-strings were 34", only the 5 and 6 strings were 35". My Zephyr/C5 5-string was 34".
The neck profiles were slightly different, the C5 was a bit fatter than the Grind - I think it would have been the same as a Cirrus.
And as you don't have to play the 1, you've got all that extra time to work out what chord he's playing. The skill I'd rely on is a bit rusty now, when I was playing in the house band at an open mic night I could read the guitarist's fingers.
I think it's probably a Zephyr. The Grind had a cut-out area on the lower horn for slap players to get in under the strings. Zephyrs did have contrasting woods in the body though, so I'm not sure. Grinds have through-body stringing and Zephyrs don't.
Zephyr 5:
Grind 5 BXP:
I wasn't going by the circuit but by https://aionfx.com/app/files/docs/l4_bass_preamp_documentation.pdf - page 3 is about the controls. I was actually looking for information on the distortion.
The stain on the back above the battery box is because the battery box lid is missing and somebody's used sticky tape to hold the battery in. I did manage to find a replacement battery box cover for a Thumb 5 which would be just the same - I may have mentioned it on here. The stains on the front - the darkening above the pickup is maybe from an arm or a jacket sleeve, don't know about the ones around the controls that look like liquid has run down it.
There's very few songs I hate. Red Red Whine (in fact any cover by UB40), Perfect by Fairground Attraction (I could probably tolerate it again by now), and anything by Paul McCartney solo or with Wings.
I shall await your verdict with interest.
One minor point - I'm not sure if the documentation is wrong or the control is backwards, but it says the Mid control on channel 2 is counterclockwise for boost and clockwise for cut.
I have no use for it but I would like to be able to do it. Not so much that I could be bothered to learn how to, mind. Probably less painful than uppercutting it.