http://www.gibson.com/en-us/Support/SerialNumberSearch/
Try the MYRRRR
M is the model year being reissued
Y is the production year
RRRĀ® indicates the guitar's place production for that year. NOTE: This number includes all models for a particular reissue year - so, for example, a 1958 Reissue serial number may include '58 Reissue LP Standard and '58 Explorer production.