I would say there are a couple things to consider. first the Merc would definately have the least amount of work to get it sweet. I myself like the two older cars which out of the two the fastback chevy is the best deal. The pontiac is a great car and would be an awesome one to restore but a shame to hotrod. The price is right on the old chev and it would be a great one to hotrod but you will be looking at alot of time and money. Budget and how soon your wanting to start driving it will be a big factor in the choice probly. You have great tastes in cars and I think any of them would be a great investment.