I have a 66 Shelby carb for sale. This is an early carb as it does not have a S2MS number on it. This one is stamped LIST 3259 and below that is DATE 581. This carb was probably used on a early car after the carryover cars. Someone put an automatic choke on the carb so it will have to be removed. Everything moves freely on the carb. The metering block numbers are 4756 and 4560. Price is $2500 plus shipping. If interested, email gandcmurphy@rogers.com Thanks.