Hi,
I've parted out a late 40's-early 50's GMC 300 that
came with a 2-speed rear. The vacuum switch was mounted to
the firewall, with the round handle mounted under
the dash. All the vacuum piping was in steel flare nut
tubing, so it appeared to be factory, in fact
the owners manual showed the exact control the truck
had. The speedo adapter attached to the back of
the speedo, and was also vacuum run.

I sold the control to a member here this summer, but he
did not want the speedo adapter. It is obvious by looking
at it that the vacuum bellows needs replaced, but
otherwise looks to be in working shape.

If you want it, you can have it for the cost of shipping.

Thanks,
Brian