So.. If I'm reading the numbers right, and the supposition about the serial number codes regarding manufacturing time frames, it shouldn't be possible to have a 1988 made Signature Edition. I'm not about to get down and do a chemical analysis on the plastic, but I'm about 99% certain from the even yellowing on the case of this one, that it did not receive a replacement case from a Signature Edition .. so if we assume that the first "8" in my serial number is actually 1988 manufacturing.. and the 2nd and 3rd digits are the week number.. then mine was manufactured between June 6th and June 12th 1988.
My understanding is that the Signature Edition was limited to the first 50,000 produced, but that would've been blown by the 4th week of 1987, probably, if this serial number system were all correct.
Anyone else with Signatures able to comment about what serial they have? Seems like if the assumptions about the first 2nd-4th digits are true, then there's some very flawed assumptions about the 5th-7th digits.