Hello Michael, I have read some of your other posts, I encourage you to take the job.
I grew up in Wyoming but moved away in 1970. I can't say for certain what the current prevailing attitudes are, but I expect they have improved since I lived there. And I think you will be quite safe.
Like any predominatly rural state you will encounter some ignorance, but nothing like the hostility that still lingers in some southern states. There is not a lot of diversity in Wyoming, but Casper, being one of the larger communities in the state, and with one of the oldest community colleges, has also always been one of the more open minded communities.
Growing up in Wyoming I encountered very few African Americans. We had only one AA family in Lander, Wyoming, the father worked for the post office. I felt like the community accepted them, I don't recall any fuss or "comments", curiosity more then anything. I think most people in Wyoming will be willing to give you a chance, if you give them a chance, and they will respect you if you stand up for yourself.
You might be interested in this thread about Casper
http://www.city-data.com/forum/wyomi...ew-casper.html
And some of these other threads on similar topics may be helpful:
http://www.city-data.com/forum/wyomi...ed-couple.html
http://www.city-data.com/forum/wyomi...-cheyenne.html
http://www.city-data.com/forum/wyomi...-i-expect.html
http://www.city-data.com/forum/wyomi...-cheyenne.html
http://www.city-data.com/forum/wyomi...ing-place.html
http://www.city-data.com/forum/wyomi...n-wyoming.html