How do I find out about a stop sign or stop sign made by G.R.S. Co. Rochester N.Y. U.S.A.?

Question

It is made out of metal and it has some numbers on it.

36727-66X, 49127-34XA, 28447-17X and on the lights 2 of them had 8-8-63 and the other one had 9-10-63.

Answer 1

Those are the serial numbers of the signs. Mostly so the officials can keep track of the signs. The dates are the dates the signs were put up.