I am not an expert on WY by any means, but I have been researching unit 27 for next fall as well. Most of the unit is Thunder Basin National Grassland (Public) and there looks to be a good amount of state/BLM land as well. If you like a paper map - I suggest the Benchmark Maps Road and Recreation Atlas. It has a land use section that shows public/private and also has a full topo section as well. There are also some good online maps, but I haven't used those as much. One you may look at is huntinggpsmaps.com - they make a map for gps that combines topo/BLM/hunt units onto one map for $79. For either area, if you call the Sheridan office of WYGF, they can connect you with the area biologist that can confirm your hopes/fears (the number is 307 672-7418). We are hoping to draw 27 this year.
Like I said, I have not been there, but have been researching heavily for 6 months. Another resource is the WYGF website. They have draw odds, harvest reports, etc for each unit in the state.
Hope this helps a little.
Christian