Michael "Coco" Polakovs was hired in the mid-1960s by McDonalds to revamp their Ronald McDonald character, originally developed and portrayed by Willard Scott. It has long been rumored that Mike also played Ronald in the first few national commercials featuring the new-look Ronald.
Here, from January 1967, is the proof...
I have also heard that the "Mr. Muscle" character pictured here was played a Ringling clown. Other early characters were played in the commercials by veteran clowns Bobby Kay and Albert White.
These photos were sent to me by Mr. Piccard from the personal collection of Mike Coco's son, Graham.
For more info on Mike Coco's life and career, please click the title of this post.