Gow job generally refers to Model T Ford open cars that have been stripped down to essentials necessary for good looks and speedy looks.
You REALLY need to search for the gow job thread. And that shadow over your shoulder? That's a customs guy getting ready to thump yer skull with a pipe wrench.
Gow job was an early name for a hot rod. They did not like the name hot rod or hot rodder, this was a name used by newspapers and magazines to describe crazy kids squealing their tires in school zones and racing around corners on 2 wheels. Real hot rodders thought the name hot rodder gave them a black eye. Gow job or hop up were the preferred terms. Gow and hop are old slang names for opium. I believe they referred to doping of race horses, a race horse than ran fast thanks to drugs, was said to be "gowed up " or "hopped up". The same name was given to cars modified for more speed. A custom job was modified for looks and style. Speed was secondary, although some customs had hopped up motors.