It's been my experience that if someone doesn't want to take specific pics for you to see problem areas then they are hiding something or just plain too lazy and don't care who they sell it to.
Sucks about the yellow one but, if he's getting up in arms about this title thing then whatever the problem is, he doesn't want to deal with it either. Just wants to sell it and wash his hands of it.
In the future, don't rely on the seller to send you pics of "all of the rust", they may only send you pics of what you can see from the outside. Ask for specific pics like the body mounts, the underside of the floors, the rocker areas, inside front of the rear wheel tubs, the tailgate hinge area, and maybe more. Do some research here on this site and learn about the problem areas, ask questions here (as you have been doing) and we are more than happy to help you along the way. It's almost as though we're buying it with you, kinda living vicariously through your situation.
And remember, keep a cool head. If you are in a position to buy a classic car/truck then in most cases you have the upper hand. Most anyone, in a private sale situation, selling a classic car isn't selling it cause they want to but rather they need to for whatever reason. If something is not right or they won't work with you, be polite, leave your number and walk away. Maybe even call them back in a week or two and see if they want to deal.
And again, don't hesitate to ask questions here.