Help please! I am refurbing an Acoustic 6x10 cab. I recvd it without the orig speakers, but i just want to find out what year it might be. Serial no. is 'W2604', which may indicate it is walnut/oak, and possibly older then '76, but beyond that, i am having trouble finding more info. It does not have the '104' designation on it, and the 'acoustic' label on the front is on the right hand side. Possibly an extension cab? Any info would be much appreciated. !!