My son and I hunted pronghorn for the first time this past October. We did a do-it-yourself hunt and were successful. If you are looking for big horns, my advice may be unsuitable for you and you may be better advised consulting others more knowledgeable on that topic. Generally, the units which have antelope with big horns have low drawing odds. Additionally, setting out to bag an antelope with big horns seems to be a high cost activity, as outfitters often lease the lands holding the big pronghorns, and the hunter desiring a big head must pay high fees to hunt with these outfitters.
Unit 24 and 23 near Gillette offer high drawing chances and lots of animals. These units also offer lots of public land, though you may need to contend with large numbers of hunters on this public land. One possible public land strategy is to avoid opening day and weekend hunting, instead hunting two weeks after the opener and during mid-week. You can get a list of land owners who will let you hunt their lands for a modest trespass fee by calling the Buffalo office of the Wyoming Fish and Game department. Call up landowners in your preferred unit and find out their terms. There is quite a bit of difference in the structure of the deals. My son and I hunted on a 1280 acre ranch about 10 minutes from our Gillette hotel. $125/gun for two days -- no other hunters on the property at the same time. My son took a buck with 13.5" horns; I took a doe because I felt rushed to take my animal, because I had other interfering plans.
Other units may also suffice. Look on the Wyoming Fish and Game site for draw statistics for all units. Consider land accessibility and animal populations in considering other units.
Pronghorn hunting is great. The meat is good, if you take care of it properly (get it skinned, quartered, and on ice promptly -- maybe within four hours or less). The hunting is not physically challenging, as the elevation is generally below 6,000' and the grades are not steep. The success rates are very high.