GG1 4877 posted:"Old Rivets" is a rail fan generated term. To be technical, the plan is restore the 4800 back to it's original number of 4899. It was designated a National Mechanical Historic Landmark by the ASME as 4800.
As many will recall, the lone PRR R (a 4-8-4 rigid frame electric) numbered 4800 was built in Altoona in1934 as the PRR was sure that their home design would best the Baldwin design based on the New Haven EP3. When testing at Claymont was complete, the GG1 proved to be the superior design and it was then designated 4800. The R1 was then numbered 4899 and then #4999 in 1940. It remained in service unit about 1960.
I am a bit surprised at the renumbering idea. I get it that 4899 was the original number, but as was previously pointed out she never saw service with it. I tend to think the number when the locomotive enters service is the benchmark, but hey what do I know?
George