I don't have any area specific advice. However, I recommend using the truck to look at everything you can, and then figure out the areas you can't see into from the truck and check them out. Pronghorn bucks with harems try to keep them in low spots so they are seen by fewer other bucks; it works on hunters in trucks too. Post-rut, mature bucks have learned - at least to some degree - to avoid open roads. One of my favorite tactics is to drive to the foothills of the biggest public land topography, then hike a contour into the wind, sneaking over each little top and glassing until I've seen the whole visible valley, then hustle across the bottom and up to the crest of the next little ridge. This works really well for a few reasons - it meets the topographic security need that pronghorn prefer, and because they tend to run to flatter topography when spooked, more times than not when you have to cross the upper end of that valley to get to the next ridge, they spook downhill rather than across the ridge. It is also efficient for you the hunter, in that the distances are smallest in the foothills between ridge tops. Finally, when you do spot the buck you want, you have a ridge to hide behind as you work closer. I have often been able to look over 50-100 bucks a day with this approach, and rarely see another hunter except for the trucks far away out on the flats.
The other advice I will offer: never let them see you. If you do see a buck that looks like it might be your shooter when you are in the truck, keep driving out of sight, then get out, circle back with your spotting scope, and look him over. Antelope go on high alert when a truck stops, and either spook, or prepare to spook, when anyone gets out. Never assume you are far enough away - if you can judge him through a spotter, he can see you.
