The plugs are not different. The harness in the car connects to the headlight assembly not the sealed beam.
To change to Euros, you simply bolt them in and then you will have to move the pins around in the car harness connector to match the pinout of the Euro headlight.
I think that there is a post here with the instructions for moving the pins around. I did mine before that post was there. I simply took an ohmmeter and probed around to find out which pin on the headlight assembly does what, then move the connector pins around.
Have a great day,