[ghnl]

There are 5-pin switches & connectors available here: Universal 5-pin Window Switch. The Alfa switch & wiring uses 4 pins - the 5 pin versions have two negative terminals to the Alfa's one. I believe the 5 pin version can be used in our cars by jumping the two negative terminals together.

 

[Anth73]

I did decide to try one of the generic pigtail 5 pin connectors I found on ebay...fingers crossed.

 

[yvesmontreal]

I believe the 5 pin version can be used in our cars by jumping the two negative terminals together.

I've done it the other way: I used the more common 5 pin switches on a GTV6. It works.