I just purchased a neglected Series 5 project. The original builder lost his bill of sale from SkyStar, as well as the Series 5 build manual so I've had to determine the serial number via other means. We found a single piece of paper (a packing list from SkyStar) with the number written on it, but I can't say for certain what the first couple of characters are. The first one might be a five (5), or it might be an "s". The second character appears to be a slash ( / ), but maybe it's a one (1).
I'm hoping that someone with a Series 5 can take a look at this, compare it to their serial number, and tell me what my project's serial number is likely to be.