Many moons ago I asked about 'shebang'. In OED I read, to paraphrase, that at one time it meant a dwelling or a vehicle or a base of operations. Mark Twain used it in Roughing It.

Now I wonder about ' I'm not leaving until the last dog is hung.'

'When the cows come home is more direct. I surmise that it means when the cows come home to be milked.

Only recently did I stop to think how very graphic 'being caught with your pants down is.

Ebbie