1968 Mustang Thermactor info

My 1968 Coupe has a 289 with a 3-speed manual transmission. According to my 1968 Ford service manual, 289's with a manual transmission were supposed to be equipped with a Thermactor air pump for emissions control. I know that many of these were removed or disconnected because they offered no performance improvement, but my car shows no evidence of having this device. I'm wondering if anybody knows anything about the history of the Thermactor and how to tell if it should have been original equipment. Thanks.