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You can see the very edge of one in the shower scene of the “Pirates” episode.
You can see one in the Tarzan outfits scene in the movie when they’re in the room for 2 days learning dances, he turns around quickly near the beginning.
When Bob is doing the Teddy Bear-Test and Mickey catching/throwing the stuffed animal, put it in slow motion...even though he’s wearing a tank top, first you can see the one on the left, then the one on the right.
You can sort of see them through the back of his shirt in the spelling bee scene in the movie.
 
Leg
In Anthology of Awesomeness, the bathrobe picture. (It’s flipped, so it looks like it’s on his right leg. Plus, there’s a shadow right above it, so you can’t tell.)
On liquidzu.com, the pictures from the Coliseum. Also, other various pictures.