The letter under the T is an E.
The VIN assignments used 64-66 are one of the many reasons why one cannot associate VINs with production. They are administrative in function.
For Model Year 1966, the Windsor plant assigned a different VIN range to US and Canada cars. In this case, it is also not correct to use 'generally sequential' as a desription as that would imply the Canada cars (200,000 series VINS) are all built late in the year after the US cars (100,000 series VINS). We can document the Canada and US bulit cars were built at the same time. Their end destination dictated the VIN range. This car carries the 99,813th VIN assigned for cars built for sale in Canada.
Thank you changing the text associated with SO numbers but there is no 'prefix' or 'extension' to the SO. That description will not apply to specialty SO numbers for situations like promo cars, Special Order or other applications. It would be much more simpler and correct to use Sales Order as description of the number and use another place/time/space to explain the SO.
The 00 SO number also tells us this car was built for sale in Canada.