Ad of the Decade was a special created by ITV to celebrate the ads of the decade and so on. Cadbury's Gorilla, the dancing eyebrows, Hovis' "Go on Lad" and even Howard Brown from the Halifax adverts got a mention. The only found pieces of media about this program are the ads themselves. Tellyads has a list of ads that were voted by 8,000 people, but the program itself appears to be lost.
There is obviously a recording of the Cadbury Gorilla being in number 5 and the eyebrows, but the program hasn't been found or rebroadcast in full. It's somewhere in the ITV archives and I don't know where there is an actual full broadcast of the program