Me too, that's the way I would go, just for the sake of cost, simplicity and reliability.
One caveat; The older VWs had a different transaxle in the diesels with a higher final drive ratio. That was so it wouldn't wind out to 7500 RPM like the gas jobbies.
Of course if you find a (bad engine) car that's already diesel, the proper trannie will already be in there and ready to go.
Thank you. Love your tagline.