I like that idea.What would the part # be I would need to order? Or from what car could I get a fan and clutch from day at the local auto wrecker? Looks to me like a 17 inch fan is as large as I can go. I found a part # on the Hayden website for a clutch fan. Were clutch fans an option in 1967?

The beauty with General Motors and Chevrolet engines is that parts are so interchangeable it makes it easy to swap things from engine to engine, car to car. I would measure the largest diameter that fits in the shround, 17" sounds about right. Go to the wreckers. I know that Vortec engines (small blocks) from the late 90's up have these clutch fans with plastic blades. These engines are in every GMC and Chevy truck.

See the photo below for the fan I use on my 454. The engine stock fan was a clutch fan but it was a 5 blade and the clutch was not working very well. I decided to get the one pictured from a swap meet. I have a few. The fan bolted straight on and was perfectly aligned with the shroud. I have no idea which GM car it came from. PM me if you like as mentioned I have a couple in the shed.

 

....another option for you to consider is just adding a electric fan in front of the rad to act as a pusher. It can turn all the time or be activated with a thermostat switch. They really work great, are excellent for slow moving in city driving, take no horsepower to turn like a big fan clutch setup does.