^^^^ Not a "shocker" for those that regularly read this board. IIRC at least two members (Nick R, ARCO) have previously posted pics here of the Ford OEM filter, and it's been posted here many times that Champ supplied the factory OEM filter.
And while the Motorcraft FL-820 may "technically" be "aftermarket", if one walks into a Ford dealer and asks for the FL-820S, it will be the Purolator made for Motorcraft filter that one will purchase, not the OE Champ made filter. Fwiw imo, the term 'aftermarket' means little in terms of gauging quality of the filter. But, the Champ factory filter fact is an interesting data point, if nothing else, I suppose.