To pull a number out of the air can be tough.Do you happen to have a shop in mind? To be very vague you can guesstimate probably in the neighbor hood of 500 hours worth of labor (or more depending) to restore A mustang (body,suspension,paint,interior,etc.)I'm vague on purpose because the car has rot(which is the only way I buy them) and when you deal with rot there are always hidden surprises.I can't really tell from the photos but are the fenders,doors, quarter panels,wheel houses,front frame rails,etc. In sound shape? I know a guy who is doing a car right now for a customer,That is soo rotted that by the time he is done replacing all of the rotted metal he will probably be in the 500 hour area by the time he's done just with the metal replacement/fabricating.Then he can proceed with the resto.