The table at Chama is 100' long. It replaced an 80-footer at 7th Street in 1919. The latter went to Cheyenne and apparently was not replaced, though from folio drawings in Hol Wagner's C&S book, it looks like a 900 2-10-2 was a real tight squeeze. If it is a three-point type, as I suspect, it could utilize the whole length for turning long engines and not need extra length for balance.
The link below shows the table with an AT&SF 4-8-4 in 1933.
As most everyone says here, it has no place at Chama, which is a historic site, and in my opinion, should have nothing the D&RGW did not once have there. Installation at Antonito would not corrupt history, but it probably isn't needed with the trackage in place there now.
A few years ago, there was an identical 100' CB&Q table, removed from its pit, near the wooden roundhouse at Northport, Nebraska. I don't know if it has since been scrapped or not. It was that long to turn the big 2-6-6-2s once used on the hill there.
Where should the 7th Street table go? There are extant Fort Worth & Denver roundhouses at Texline (derelict) and Amarillo (beer storage), Texas, but I do not know what their turntable length was. Texline might have had a 100-footer, as I think the USRA 2-10-2s ran down that far. Thus far, no one seems interested in preserving these rare structures, unfortunately.