...what year truck,berryboats?
If your talking 51-53 era then I drilled out the pivot rivet, and then took the nut,springs/washers off the bottom of the stem that sticks through the bottom of the vent frame.....
If the vent frame is still in the door then there is a little access hole to take the stuff mentioned above off. Once your finish you put in a new rivet......which was not easy for me so I took a rivet to a neigbor machine shop and had them cut me a few "bolts" that were just like the rivets but were threaded on the end and use it instead of a pivot rivet.
Hope this helps
