Spot and stalk with a bow is very difficult. They will see you hundreds of yards away. If the terrain is completely flat, it is almost impossible. A blind over water might be your best bet. Sorry I could not be of more help.
New Mexico seems like a "pay to play" kind of state. I don't have the money for a landowner tag, so I don't have much experience with them. Since the draw ended awhile ago, I would assume landowner tags are going fast. Sorry I could not be more helpful.
Get some instant cold packs and put them in your backpack. They stay cold for about 20 minutes. I have gotten dangerously overheated before and I do not hunt in hot weather without them. If you get in trouble with the heat you can put a pack on your neck for a few minutes and it will cool you...
I do not want to be discouraging, but I tried to spot and stalk pronghorn with a bow once and I am never doing it again. It was brutally hot and I never got close. I had around a dozen failed stalks. The terrain was very flat. I don't see a 40yard shot happening. I would save the points until...
Both MT or WY would work. You can get it done in a low point unit, but if you are driving from Maine, you might want to go for units that need a few points.
I hunt in low point units and they are always a zoo. I don't want to be discouraging, but private land might be your best option. Also, be aware that pronghorn and deer open the same day and depending where you are, there might be deer hunters as well. Good luck.
New Mexico might have some landowner tags, but I assume they are sold to outfitters. I don't have the money for landowner tags so I am not exactly sure, but New Mexico seems like a "pay to play" kind of state. Sorry I could not be of more help
I bow hunted one of those units last year. It was brutally hot. After every failed stalk, I have to sit in my car and cool off for a while. Be prepared for the heat and you should be ok. I like to have some of those instant ice packs in by bag incase I get dangerously hot.