The VIN location on a 1971 Ford Step Van will depend on the specific chassis and body configuration. It's *unlikely* to be in the same place as an F-150's VIN.
To find the VIN, you should:
* Check the driver's side dashboard: This is a common location, but not guaranteed for all Step Vans.
* Look on the driver's side doorjamb: Another possibility, although less likely than the dashboard.
* Check the firewall: The area where the engine compartment meets the cab.
* Consult a 1971 Ford Step Van owner's manual: This would be the most reliable source.
* Check the vehicle's title or registration: The VIN will be listed there.
If you can provide the chassis or model number of the Step Van, a more specific answer could be given.