This was the RR's first gas-mechanical, before the more famous one that went to the D&RGW. Found at a fertilizer dealer, it had been converted to standard gauge and required much rebuilding. Both old and recent photos here:

http://www.ngdiscussion.net/cgi-bin/NGD ... read=82057

Scroll down on the NGDF. Lots of nice Sumpter Valley photos posted recently.