That first Silberblue is a Series 1. Easily denoted by the body colored transition panel between the cockpit and convertible top cove. That is the gas tank. The series II moved it into the trunk among other refinements. The second is chassis #70079, which is important in many ways. That’s Hans Stuck standing next to the car he used as a BMW press car for months as well as a picture of him driving it in one of the European Hill Climb races he entered of which he won his class both times. The other significance of the car is this is the one that is currently restored famously by BMW sitting in Munich which had previously been owned by Elvis Presley.
…and now you know!
Cheers
Dave