First I feel bad saying coconut head, but then who said life was fair. Marsha has an excellent vocabulary but there are many American euphemisms and slang that are beyond her reach....until she met me.
Shinola - According to Wikipedia, Shinola is a brand of shoe polish. There is actually a history with this made up word. Shinola was imortalized in the colloquial English phrase, "You don't know S@!$ from Shinola. Similar expressions include, doesn't know his ass from his elbow or Sir Henry Wood's doesn't know his brass from his woodwind. For me its a genearal term and a nice way of saying its all a bunch of BS.
Belly up to the bar - it means to put your money where your mouth is......please don't make me explain that as well.