Mick was next in and when asked his occupation replied, "Diesel Fitter."
Since a diesel fitter was a skilled job, the clerk gave Mick 160 dollars a week.

When Paddy found out he was furious. He stormed back into the office to find out
why his friend and co-worker was collecting double his pay.

The clerk explained, "Knicker Stitchers are unskilled labour and Diesel Fitters are skilled labour."
"What skill?" yelled Paddy. "I sew da elastic on da knickers and thongs, then Mick puts 'em over his head and says: "Yep, diesel fitter."