Gibson serial numbers are even more interesting, because you can find out the specific date that your instrument was completed! Here's how:.Serial number coding for Mexican-made instruments is largely the same, except they will start with an M.The remaining digits are important for product identification, but the first few characters are all you need to determine the instruments age.The second character will usually be a number.For US instruments, the serial number will start with a letter.Serial dating is easiest for instruments made in the USA or Mexico, but is also possible for those made in Japan, Korea, China, and Indonesia. First, narrow it down by the country of origin.Here's a brief rundown of how to do it, plus resources for more information. Well, good news it's very easy to figure out the age of Fender and Gibson instruments from the last 30 years. Ever wonder exactly when your favorite guitar was made? You sort of remember when you got it, but you want to really know its history, especially if you're not the first owner.