This is a very hard question to answer because everything depends on: your level of restoration experience, the current condition of the vehicle, shops and supplies you use for your restoration, and what quality of restoration your looking for. The 67 is a great Mustang. Start looking through catalogs such as:
14833 Lakewood Blvd
Paramount, CA 90723-4511
You can find many more from magazines such as Mustang Monthly
Set a goal. Do you want to go through a frame off restoration, or do you want to keep everything in it's original condition yet still drivable? Believe it or not, most collectors would rather see a car with scuff marks and use on the original vehicle with the original paint than a perfect restoration on a car that nobody can tell what type of torture the car was subjected to.