Put that in your measuring scenario above and you'll get more accurate guestimates.
I can't give you details as to what to look for on a good scoring goat but I can tell you that you will know it when you see it. I know that's what you really aren't asking but when you see a good buck, you will know it.
I'm pretty sure I know where you will be hunting and if it is dry you will see a bunch of bucks and you will know when to shoot.
Also...Don't overlook the coolness factor as being a reason to shoot. Antelope are so unique and some will just trip your trigger.
I believe field judging antelope is very hard. I am no expert on field judging but have attached a picture of four Lopes I've shot. Two make P&Y book (67) and two don't. Care to guess which two make it?
A big hint when judging mass is where does the front of the horn end in relation to the eye. If far fwd, greater mass.