using VIN lookup sites to probe for actual production numbers

[xsexcess]

Has anyone ever tried putting high numbers into the VIN lookup sites to try and probe for actual production numbers? For the XS-1 as an example the number 7,000 produced is used because the XS-1B sequence starts with that. But what if they only produced 6,000 for example? The one in my barn is in the 5700 range so I know they went that high. Who has the highest serial number XS-1 on this site?

Any recommendations for a good site to use?