Finally got some real black grip-tape to use on the Zenit and, importantly, mirror the carbon-fibre underside. I say “real black” because most of the grip-tape I have found to date has actually been various shades of grey; which is annoying when it is universally sold as “black”.
Finally fond real black sold by the ever-excellent and helpful Skate Deluxe (Monster Grip Tape Heavy). It is heavy grip which a little too rough for my liking, but as ever is if form over function. Also being heavy grip it is more difficult to cut and trim, but the end result is not bad and confirms the single mirrored top and bottom design works well.
I will stay on the lookout for ‘real black’ lighter or medium grip-tape, but for now, it works.