I have a few questions too:
Based on the photos I have seen on the "on the dash" site, this symmetrical style dial belongs to the "economy" Monza. This would be consistent with the fact that the caseback on the auction reads 110.511, which corresponds to the chrome plated version of the economy monza, again according to Jeff's table. Is it possible that the caseback came from a different watch? That would also explain the high serial number as well. Just stabbing at the air here but something seems odd about this watch...would love to see better pics of it.

: Putting aside the oddities of the auction, let me ask a couple
: of questions about the watch itself. Is it unusual to see a
: Cal 12 Modena? I seem to recall that most of the Modenas that we
: have seen have been Cal 15s. If the theory has been that Heuer
: started making "Modenas", and then changed the name to
: "Monza" around 1977, then this one has a really high
: serial number, at 393 660. We know that the serial numbers do
: get a bit jumbled, but 393xxx is far higher than most of the
: numbers that we see for 1977 (and the other Monzas). Could have
: been a mistake in the eBay listing? Any other explanation for
: this high SN? Always good fun to piece together this
: information!!

: Jeff

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