I've been really thinking about it.. I know it could be done.
I've had this car down to its shell.. I know 90% of the holes in the body, and it wouldn't be hard to seal them all up..
I'd take alot of sheet metal and make the whole underside of the car smooth.. aside from the driveshaft, and fill it with expandable foam.
I'd get a small motorcycle sprocket that has the same bolt locations as the driveshaft.. Bolt it on in between the shaft and the diff. Get another sprocket and PTO shaft.. And have the shaft go under the diff. I would attach the prop to the PTO shaft when needed.
I'd make a snorkel and I'd seal off all the electronics, the transmition, and engine. I'd also fill most of the engine compartment with foam..
I'd also make a rudder that would attach to a couple levers.
I know it can be done.. I have the time, the will and the knowledge to do most of this.. but I don't have the money..
Anyone want to help build the first amphibious Subaru wagon? lol