Here is where the importance of the Model year part of the code comes in.
The March 2005 production was 6Y1000xx and you are comparing those numbers to the 7Y100xxx Sky numbers. Different model years are involved here.
The last 6 of the VIN are started over at 100001 with EACH MODEL YEAR. This is why you need to use the last 8 of the VIN.
The last 8 of any GM VIN are a unique identifier that will only reference a single GM car. The last 6 of the VIN are useless without the model year and plant identifier.
As a side note all 6Yxxxxxx cars are Solstice LE5s. There were no LNFs made until mid-model year 7Yxxxxxx. There were no Skys made with 6Yxxxxxx, as all Skys were 7Yxxxxxx and up.
Dave, I see your point and I agree that eight (8) characters must be used. So, in looking back at my search of those missing five numbers in December 2005, I was using 6Y1000xx and finding a March/April 2005 manuf. dates. To find those missing units for 12/05 of my search, I must use 7Y1000xx. My attempts with those changes have not produced those units, so stumped on finding those for now.
I also note you state each model year's production starts with 100001, etc. Somehow, I had thought that was not happening, so i stand corrected on that important point. Thx
Also, in reviewing your previous posts, I believe I understand production went something like this:
1) the first Solstice cars 6Y100001~6Y100700 were produced starting around approx March 2005.
2) then promotion cars 6Y000001~6Y001000 were produced and spoken for in a 41 minute sell out.
3) following were Solstice ~6Y100701 and up began again for an unknown number of units.
Yes, this topic can be confusing!