Hey sigpros, we've hunted Wyoming antelope 7 or 8 times, just my two cents.
Next year is looking like a tough year for trophy antelope hunting. Most of the best antelope country in Wyoming is now classified as "severe" or "extreme" drought. Antelope horns begin to grow in November, and so as of today you already have the "tops" of the horns two months into their growth cycle. My sons have max points and we really wanted to taken them next year, but decided to hold off for one more year. Here is a link to one drought map:
http://droughtmonitor.unl.edu/monitor.html
Second, just a thought, but you will be driving through about 200 miles of prime antelope country (with great public access) to get to Unit 90. While I understand Unit 90 is a good unit, most of the traditional antelope hotspots are further east. Carbon, Sweetwater, Freemont and Natrona counties are the best counties for trophy class bucks. Units 60, 61 and 64 are three of the best units but the adjacent units can be just about as good.
Don't hunt the opener (a circus), hunt two weeks into the season, at least after the second weekend of the season. Also midweek is best when the locals aren't out. After October 1, most of the locals are deer hunting and done hunting antelope. If you go after the second week of the season, and after October 1, you will just about have the antelope hunting to yourselves. It is much more fun hunting antelope that aren't being run around by other hunters.
Often camping spots for Wyoming antelope is just a flat spot in the desert, or maybe behind a ridge to act as a wind break.