Thanks for creating the Utah tracks. I will plan on using them on a future ride.
I see there are some discrepancies between the official map and the Benchmarks. One is between 89A and 89. The BM map shows the GWT on roads a few miles east of your tracks. But it is obvious from you maps the GWT is more of a corridor than a single fixed route.
A good way to buy Benchmark maps is to order them online. You can search around for the best price and buy a few at a time. IMHO they are a must for trip planning in the west.
I copy the relevant pages and mark the route and bring them with me on trips. Then I save the copies and reuse them on other trips.