Not to belabor the Trinidad --> Amarillo --> Trinidad discussion but I've also made this trip in both directions a few times in both my Model S P85D and Model S 90D. I agree with the points
@PLUS EV &
@reddy made and will also add that it's trickier than it might obviously appear on the northbound trip (Amarillo to Trinidad) due to the fact you have to cross Raton Pass very close to the end of the journey.
Amarillo, TX elevation = 3,605'
Trinidad, CO elevation = 6,010'
So while it appears you only have to overcome a 2,400' elevation gain, in fact you need enough energy to go from elevation 3,605' (Amarillo) to elevation 7,835' (Raton Pass). Once you cross Raton Pass, it's all downhill into Trinidad and you actually gain energy for the last 12 miles of the trip but you need enough energy near the very end of the trip to make it over and across Raton Pass.
Bottom line, if you're going to make this trip in an 85 or 90 you need to start out slow from Amarillo, watch the prevailing winds and adjust for them and probably consider another route (or plan on charging in Dalhart along the way) if it is very cold in the dead of winter.
Mike