Don't recall the last year with wood, think it was about 1996 or so.
The serial numbers go like this:
G-391234
First letter is the model. G=Grandee, and there are a mess of other ones.
first number after the model is: 3=made in the third quarter of the year.
Second number is: 9=made in 1989. A=1999, B=2000, C=2001, D=2002, E=2003, F=2004, G=2005
Last four digits are the serial part.