I have a couple of questions.

Why does Chevs of the 40's show 1947-53 Tail Light Assembly -Panel & Suburban
Don't these bullet directional lamps assemblies fit on all 1947-55 single unit bodies?

Jim Carter's Tech article - Panel Truck Tail Light -- shows lamp assembly part# 916877.
Isn't this the same lamp assembly used on all the 1947-55 single unit bodies?
It does say, These small bullet shaped lights were actually from a 1939 Chevrolet passenger car.

Then Jim Carter has this Tech Article - 1947-1955 Tail Lights read the last paragraph.
Its says, Turn single option today 1947-1955 single unit body.
It does say again, These small bullet shaped lights were actually from a 1939 Chevrolet passenger car.

Then there is this RPO 249 Dual Tail and Stop Lamp In the 1947-54 Factory Assembly Manual.
Which shows lamp assembly part# 897461 LH and 897462 RH.
Is this the same as part# 916877 ?

Here is what I know is a original 1954 Lamp Assembly RH , DURAY.

This is what it shows in the 1929 - 1957 Chevrolet Master Parts & Accessories Catalog Group # 2.679
It shows 1954-55 part# 897461 Left and 897462 Right. But not part# 916877
It shows 1939-52 Part# 927639 L, and 927640 R
Where there different bullet directional lamps assemblies made just for the 1954-55 single unit bodies?

Here is rubber Tail Light Pads that are to go in between the lamp housing and the truck body.
There is also a reinforcement plate that goes on the inside.

Jim Carter shows them as 1947-Early 1955 (Accessory) Panel and Suburban

The difference in parts numbers may have something to do with one wire or two wire lamp assemblies.

Also if you ordered the RPO 249 Dual Tail and Stop Lamp for the single unit body truck.
Did they put the Tail/stop Lamp on the rear left barn door?