I was just reading through Gordon Chappell's:"to Santa Fe by Narrow Gauge:the D&RG's "Chili Line"". It's actually a reprint from the Colorado Rail Annual 1969. On page 52 (actually unmarked) there's a detailed map of the various trackage in Santa Fe.It clearly shows the relationship between the various RR's.
Aside to CJ: It states that the roundhouse by Hickox Avenue was dual gauge and shared by the D&RG and the NMC.