I'd try to get the correct Carter automatic choke too. Getting it, and adjusting it correctly is key to having it run right, and not running too rich or too lean either cold or hot. Finding the correct air cleaner and attachment bail is getting a bit tougher to find also. Check your accelerator linkage to make sure it hasn't been modified for that later carb. You'll also probably need to source the rubber connector for that linkage unless it's coming with the carb. It's also possible that you may have to adapt the fuel inlet line and/or fitting to fit the replacement carb.
