I also have a 52-3100

Should have vent windows in both doors

Should have a cowl vent on the right side thats for a fresh air heater thats mounted on the kick panel over that vent if you're truck was shipped with no delux heater the kick panel will be blank with no hole in it.


Look at the distributor and right next to it on the engine toward the back of the truck is a flat spot and on there is some stamped #s not cast #s list that # and we can tell you all about what engine you have .


Pete