New Mexico Central

Okay folks, here's some questions that start off narrow, but quickly turn to standard gauge.
Whilst reading Richardsons new book "Rio Grande - Chasing the Narrow Gauge" (more on the book later), he makes mention of the dual gauge connection between the D&RGW and the New Mexico Central at Santa Fe.
Did the Rio Grande interchange with the Santa Fe also?
As for the NMC, what liitle I've found about it shows that it went southwest, then south out of Santa Fe, where it crossed the AT&SF at Kennedy.
It then continued south, crossing the AT&SF again at Willard, and on to Torrance, where it connected with the El Paso & Rock Island (later SP) line from Tucumcari.
The AT&SF appears to have taken over the Willard to Kennedy segment, but used the line from Lamy to get into Santa Fe.
What was the New Mexico Central?
How long were they in business?
Did the two lines go north into Santa Fe at the same time?
As for the book by Robert Richardson, get a copy.
Lots of new photographs, very good printing and paper quality, and quite informative text.
A good addition to any library.
sda