How do you insatll power door locks and power windows on a 67 mustang?
You might find some aftermarket outfit that offers such items. If you find them, they should have instructions on how to do the installation; if they don’t detailed instructions, walk away. 67 Mustangs did not come with either accessory. And I have done enough fixing window cranks and rollers to say that there isn’t a whole bunch of room inside those door panels. But on the other hand, today’s power window units are getting smaller and smaller so anything is possible.