Meaning of "Mickey the Boob"?
"You just listen to what I said. I want to play Mickey the Boob."
"It's good to play Mickey the Boob with you."
from Money Talks (1972, US) (IMDB, by/with Funt the creator of Candid Camera docucomedy/docutragedy/documentary) talking to Dominick a knife dealer, from on Amazon Prime with a/my EPIX Channel free trial.
The major search engines Google, Bing, and Yahoo do not have any definitional information in English, even though it's been 50 years.
Speaking as an American born American citizen American English speaker (said in as single breath/string like many presidents at a debate would) with an exactly 3.69 GPA High School Diploma, and a year of University (like Mark Zuckerberg), who had both parents speaking legal and engineering English 100% of the time, my best/educated guess is that "Mickey" is the male Mickey Mouse and "Boob" is obviously the female human part, which is then confusing the process because of the male/female dichotomy differentials (which could be the meaning is pejorative and condescending maybe a curse word too?), so the meaning is difficult to define by ear.
In this context he is likely referring to a male character who is by nature foolish and unfortunate. It would have nothing to do with female anatomy.
From the source below we see what may be the first use of the term Boob for an individual. The character himself was a klutz, and the cartoon would always end up with Boob doing something disastrous in his effort to help.
As for Mickey, the name was in use long before Walt Disney and the mouse. Excellent work by the Disney folks in Google and elsewhere makes this tough to dig up. Many families with the name came to the US from Ireland in several waves. In addition the term "Mic", a mostly pejorative term, was used to refer to the Irish as noted below.
The conversation above may mean only that he wishes to be the generic fool working for his friend.
http://rube-goldberg.com/wiki/characters.html
https://en.wikipedia.org/wiki/Boob_McNutt
https://www.houseofnames.com/mickey-family-crest
http://www.rsdb.org/race/irish