32SII ROM versions and serial numbers - any way to correlate?

[Dave Britten]

I'm keeping my eyes out for a USA or Singapore 32SII, and I want one with ROM version 1 (i.e. no - or fewer - fraction bugs). My USA ROM 0 unit is 3116, so 1991. My Indonesian ROM 1 unit is ID1, which I believe is 2001. So the update happened somewhere in that 10-year span, I'm guessing closer to 1991 than 2001. Anybody have a few data points to add so we can narrow it down? Then I'll have a better idea of serial number ranges to look for.