the tag is the best ID - identifies the exact configuration of the carb - take it to the parts house, tell'em what engine it's from, and they'll know exactly what the carb is - if it's a one barrel it's B, 2 barrel= 2G, 4 barrel= 4G, if it's auto choke there's a C as well, like 2GC - pretty simple - any other number is 'generic' and doesn't tell you the jets and application, so treasure that tag in case you need to buy a replacement some day!
Bill
