Hi Udi,
yes, you're right - the Weber 38DGAS were originally fitted to 3,0-l Essex V6 and can be used without rejetting on 2,8-l Colongne. On Pintos it would run after rejetting the carb.
I dont know, which jets you need for the 2.3 Colongne, but try contacting this guy: [Ebay-Auction]. Maybe he'll help you.