1934 Terraplane with disappearing vent installation. HELP Please!!!

I know of no such manual.  Your best bet's to contact someone with a similar set-up who lives within a few hours of your home, and see if you can drive over so he / she can explain the operation to you, firsthand.  Where are you located?  Maybe someone with a disappearing vent-equipped car will read this and then contact you and offer their services.

I believe the glass itself resides within a thin steel frame (chromed finish) that has a pivot rod on the underside.  You unscrew the little pivot screw at the top of the frame, then turn the crank handle so the vent window opens partly. Once it is clear of the opening in the cradle assembly, you can tilt the top part of the vent window out of the cradle a little bit.  Then raise the vent window glass and frame upward, and the pivot rod pulls out of the gearbox (on the cradle), and out comes the glass and frame.  A competent glass shop should be able to trace your old glass, and make you a new laminated glass insert.

The 1934 parts manual must have an illustration of the entire cradle assembly.  Assuming you're an H-E-T member, you have free access to this manual (to read, or to download).  Go to the "Library" drop-down menu on the H-E-T Forum which is at the Club's website https://hetclub.org/ and see what's available in the library.

There were two basic cradles, one for convertibles and one for sedans.  I think the cradle installs from within the door (if my memory's correct), and then slides upward on the tracks.  First, remove the door upholstery panel (there are screws around the perimeter of the panel  which hold it to the steel door). 

Be careful when handling the pot metal frame, it is made of Unobtainium and no one is making reproductions!

Here's one in operation: https://www.youtube.com/watch?v=--RcNAKPnnA

Here is a simplified explanation of how it all goes together.  I cite the 1937 parts manual because I couldn't find a '34 parts manual in the H-E-T  on-line library.  But these disappearing vent window mechanisms are similar from 1934 to when the windows were discontinued.

For views of the door interior, see page 116 and 122 of the 1937 parts manual (available for download by members, at the H-E-T website). On page 122 the "disappearing type" cradle on the right, is the type that goes up and down in the door. (The closed car version is shown.  The convertible version has a cradle that is more squared off at the top.)  Also, you might want to open this video so you can refer to it:  https://www.youtube.com/watch?v=--RcNAKPnnA

Back on page 116 you see the door interiors.  The right door does NOT have the disappearing vent window, (all you can do is crank this window open) but generally the layout is similar.  If you compare with the right photo on 122, you see that the one on page 116 does not have the squiggly "wing operating cam" as yours does.  That cam allows the window to slide down.  But the photo does give an idea of where the various components are placed.

As I recall (from the last time I was inside my door, 40-50 years ago), the first thing that goes in your door is the regular (up / down) window track nearest the door latch. Then the (regular up-down) window (which consists of the glass in a steel channel) goes in so that is easily slides freely up and down in the tracks.

Then the regulator mechanism bolts in, but you will have to manipulate the "scissor arms" with the crank handle, spreading or retracting them until the round clips fit into the slots on the L-shaped window support arm (#10).  Then it is time to mount the vent window cradle mechanism which actually holds the vent window.  But this, too, has to be manipulated so that the various scissor arms so that they fit into the vent window cradle slots and properly raise, lower, and swing open / shut the vent window.  When that is been done, you may bolt the vent window mechanism into the door with the pan head screws.

You will still have to mount the vent window itself, in its metal frame. As I recall the lower pivot of the vent window frame is lowered through the opening in the garnish trim at the belt line, so that it engages the gear that's hidden down in the door.  Some tilting and manipulation is called for.  Then the top pivot of the vent window frame is swung around and pushed into the pivot hole in in the top of the pot metal cradle.

Very hard to explain.  But if you lay all the components out on a table near the open door of the car, and then study the illustrations in the shop manual, I think it will begin to make sense to you!