Appears to be a vertical headlight assy. GE bulbs Top bulb is a 4003 export and glass face reads drive left. Lower bulb is a 4001. Bracket reads SAE H-66 HL. Hall-9A.
There are 4 of these. They were wrapped in newspaper dated 1965. They have about a 5” diameter with a 2.125” center diameter on two of them. The other two have a 2&7/8” inner diameter.
That is also what I believe it is. I haven’t removed the cap yet. I agree with you but wonder what might have used this dual purpose tube. Thank you Nick