Quote:

RM21 H9B 290xxx- VIN "B" plant would be Hamtramck. RRs were built at A-Lynch Road, G- St, Louis or E- LA. My guess is the "6" Is a G for STL due to the SPD and VIN



Oops, my bad...I knew the 6 was a typo, I just assumed it was a "b". You're right, G does make more sense.
Is there a web site that shows all the interior codes?