310 410 384480
Note: I am not 100% confident in this location. I do know the signal appears strongest closer to Kremmling, and is located somewhere that the signal can get out in three directions including pretty far to the northwest. The reason I favor this site is that the AT&T 38448x numbering range in the Grand County area appears to all be built on Union Wireless sites. For example 384485 southwest of Kremmling is on the San Toy Union site and 384486 west of Lake Granby is also a Union site. Thus it seems likely that 384480 is also on a Union site and so this Wolford Mountain site would fit what we know of the coverage area. It also does line up fairly well with the coverage of the Union 3G site at this location.