To give you an idea of how many cars had their bodies made by Holden, here is a list (not a complete list) of makes that had some or all of their production bodies made by Holden
Buick, Pontiac, Oldsmobile & Chevrolet were the big 4 GM brands plus Oakland, Vauxhall & Cadillac which were also GM vehicles
Other American makes included Hudson, Essex, Dodge, Durant, Dort, Chalmers, Rugby, Chandler, Studebaker and Nash
European cars included Fiat, Austin & Morris
A little known fact that Ford had bodies made by Holden up till 1925
Imagine the irony of owning a Ford with a body by Holden nowadays!
Ken