Thanks. I haven’t tried enhancing the photos yet, but I couldn’t make out parts of the numbers on the tank and didn’t find a fifth digit at all. I have a feeling the tank was sandblasted in 1994 and part of the numbers wore away then — the surface they’re on is pretty uneven.
It looks to me like the number is 2130 (and one more number, of course), but I’d be happy to be proved wrong
