Below is the trip I did last summer, and the trip that my brother is doing right now (he is in Northern California now).
First question, do you have a JESLA or other method to get 40 amps from a NEMA 14-50?
Second, SLOW DOWN !!! Find a truck and match his speed... 55-58mph is typical. Do NOT draft too closely and compromise safety.
Third, run the air conditioner. It is VERY efficient and it is running anyway to cool your battery. The very few miles you'll lose from cooling the cabin will mostly be offset by having the windows up.
Fourth, I think you are using GOM values for your trip, and that is never going to work well.
NOTE: I have a Tesla Roadster adaptor
From my house in San Diego:
84 miles - S. Coast Plaza - ClipperCreek (CC) 30a/208v -free
61 miles - Malibu Civic Center - CC 30a/208v- free
31 miles - CSU Camarillo - CC 30a/208v - free
56 miles - Rabobank Goleta - CC 70a/240v - free
98 miles - San Luis Obispo Embassy Suites CC 30a/208v - free
135 miles - Rabobank Salinas CC - 70a/240v - free
117 miles - Renaissance Club Sport, Walnut Creek, CA - ChargePoint 30a/208v $$$
71 miles - Davis garage, 4th/G Street, CC 70a/208v free
91 miles - Berry Patch Restaurant, Orland, CA, CC70a/240v!! First Roadster connector free
151.6 miles - Comfort Inn, Yreka, CA, CC 70a /208v Roadster connector free
121.8 miles - Canyonville, OR, CC 70a/208v Roadster free
117 miles - Halsey, OR, AeroVironment (AV) 30a/208v J1772 needs AV key fob to work $
83 miles - June 25 - Portland, OR, CC 70a/208v Roadster free
103.2 miles - June 25 - Maryhill Washington State Park - NEMA 14-50 50a/240v with JESLA 240v/40amp EVSE, $$
100.6 miles - June 25- Kennewick, WA
