i caught something new in The Mandella Star Wars effect

My friend mentioned that in 1978 the oscars had a segment where c3po had a silver leg and than i saw this taking place in the movie as well, i never noticed this as a child so i compared movie posters, toys, and special appearances
Oscars 1978
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but than i also saw a clips of the 2016 oscars and he is fully gold: [link to www.youtube.com (secure)]

Also look at this vintage psa:
[link to www.youtube.com (secure)]

now look at the cereal commercial:
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Than when c3po visits sesame street:
[link to www.youtube.com (secure)]

Gold leg commercial:
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