Railway Express Agency (REA) was the UPS of the day. Their green trucks with red wheel rims were everywhere. Set up by the US government by merging private express companies in WWI and later owned by the railroads, they primarily used the passenger train network of the day to move small packages around the country in "head end" cars.

Unfortunately as the passenger train network dwindled, so did they, going out of business in 1975. By that time UPS and others had taken over the function quite well.

The Oldsmobile is fitted with after-market seat covers, a big automotive item in that era, advertised to be a cool alternate to the wool or mohair upholstery that showed wear all too quickly.

Can any of the Shorpy Sleuths pin down the make and year of the REA truck?

looks like an unintentional double exposure made before the main image. Easy to do when you're setting up the camera and checking the shutter.

The reflection of his face suggests it was shot through a window that was inches away at most.

The reflections in the car looks like it was shot in the open. It even looks like the outline of spectacles can be seen in the car door. Maybe those are just swirls in the paint? And yet, there are reflections of window signs clearly visible.

His reflection in the wing window conflicts with my sense of perspective vs. his reflection in the body.

Perhaps it was all coordinated by a guy named Escher.