The doors dont match, I assume they were probably just switched out at one time, but one door has the vent window, and the other door doesnt have the vent window?
Other question...
The cowl (between the hood and the doors, one side has the slotted vent into the side, and the other side doesnt have this vent.
Ive never seen only one side with the vent, but thought this was one piece... did they come like that?
This also has a 4 spd on the floor, and I assume a 216 engine. Any obvious way to determine what engine it has?
Most of your questions were answered, above.
In 1952, both doors would have had vent windows.
All Advance-Design cabs had vent louvers on the right side cowl (for the optional Fresh Air or Air Flow heater). Vent louvers were never placed on the left cowl; however, from 1947-1950 there was a ventilation "door/scoop" (left side cowl ventilator) on the driver's side-cowl (not continued when vent windows were provided in 1951).
Post the codes found on the block and head and people will help to ID your engine.
