It could mean nothing more than when the original Ford motors wore out in the '60s or '70s the Europeans swapped in a motor that was more readily available at the time. Pretty common stuff. Of the fifty 100S Austin-Healey race cars, seven of them had an American V8 swapped in at some point, including this one that's coming to auction:
https://news.classiccars.com/austin-...sdale-auction/