Luke, here is another option for you. I have no experience with it in Wyo yet, but I've used it plenty the last few years here in ND and it's a wonderful thing to have. I'm heading to Wyo this year for antelope and would not go without it, so I did upgrade to the Trax West + option....Includes many states, for a reasonable price.
http://www.koutdoorproducts.com/index.html
Just as an aside, if you purchased the pre-loaded chip from http://huntinggpsmaps.com/ you can now update online, it was pretty easy even for a computer dummy like me.
Go to this page and purchase the update, it's listed under other maps.https://www.huntinggpsmaps.com/Web_Store/MapStore.php# From there it is just a simple download provided you have your original chip installed in the computer. I did have problems with the trial version when I tried to use VISTA so I used the wife's laptop with Windows7. Worked like a champ, now if I could figure out how to load it on the laptop, life would be great!
Bob