Kevin-
The best advice I have is to buy a car already restored. It's rare that someone can get their investment (money or time) back when they sell a "done" car. The buyer almost always gets the better end of that deal. This is especially true if you are going to be paying professionals for some or all of the work.
Here are some general rules to follow on your quest:
1. Learn as much as you can about the particular car model you're looking for. Many sellers don't know what they have, some do but will misrepresent what they are selling. You'll need to see through that ignorance and/or BS. It sounds as if you're taking the right steps in that regard.
2. Decide ahead of time what you want, and don't be tempted to settle for something else. Inevitably, you'll be sorry you did.
3. The more original the car, the more you'll pay. In the long run, it will be a better investment. If, however, you just want a "driver" to enjoy, and you won't be tempted to spend a fortune making it right, save your money and buy something that may have a wrong engine but looks good.
4. If it's a choice between a car that needs body/paint/interior work but is mechanically sound, or vice-versa, choose the car that needs the mechanical work .It's generally cheaper & easier than paying for cosmetics.
5. When inspecting a car, try to find someone with experience to accompany you. You'll benefit from their advice, and they may talk you out of an emotional decision. It may even be worth hiring a professional appraiser (especially if the car is a distance away). A few hundred $$ up front may save thousands $$ later.
6. For the actual inspection, wear grubbies and get down in the dirt. Look for leaking fluids. Poke around the frame, floors and trunk for metal rot. Car may be all shiny up top, ugly underneath. If the car runs, watch from behind as it drives down the street. If it moves sideways like a crab, the frame is bent.
7. If you see a lot of aftermarket Pep Boys/Advance Auto type of replacement items, it probably means the seller or a previous owner was not concerned with preserving the car, or was cutting corners elsewhere, as well.
8. Regarding your engine concerns - unless the block is cracked, most engines are rebuildable. If the engine is not running, try turning the crank pulley to make sure it's not frozen. As for the numbers, check
Wallace Racing for good info on casting &stamped numbers. Unfortunately Pontiac did not start stamping the VIN on the block until 1968, so you'll have to go by engine casting and date code to judge if it's original to the car.
9. We are very fortunate in the Pontiac hobby to have easy access to documentation. Most responsible sellers will have already purchased copies of the original invoice from Pontiac Historical Services (PHS - see Links section). If not, they're readily available for $35-$50 - an excellent investment. I wouldn't buy any Pontiac until I've seen the PHS papers.
Hopefully some other members will chime in with their suggestions. We're still a small community her, but it looks like we have a relatively strong contingent of '67 owners. I would shoot them an email with your questions. I suggest you also post questions on the forums at
Classical Pontiac and
Performance years. Both sites have a large community of very helpful Pontiac guys.
It's a great thing you're doing for your parents. I wish you the best of luck in your search.
Jack