OEM Door mount mirror arms - '56 GMC

[WeDyno]

My door mirrors arms are different. The Left hand one is taller and has a thicker stem than my right hand mirror arm. Is this correct?

 

[Bill Hanlon]

It has been 28 years since my '57 GMC had factory mirrors, but I remember them being different. I can't remember what was different about them. It would make sense that if the driver's mirror was on a longer stem that stem would be larger diameter.