Getting ready to install my windshield and I bought the 2 little spacers for the bottom edge. When I place them in the channel they don’t stick up any higher (or even as high) as the trim clips, what am I missing?

you may have gotten the wrong ones. Window spacer rubbers are used in two places & are shaped differently.
The ones used to support the Rear window are long & thin. The ones used for the windshield are like small rubber blocks
Where did you source them?

Pictures would be good if you can.

front and rear are both the same part number for the glass to rest on do not have to be as high as the clips

your part #91454190710 rubber spacer is for the rear window & the part for the front glass IS different (taller shorter thicker).
Ill see if I can come up with an image

A couple pics…….I guess I don’t understand their purpose if the windshield is going to bottom out against the trim clips before it ever touches the spacer. It seems to be from the Dept of redundancy Dept.

Click to view attachment

Here’s the spacers butted up against the clip and you can see it’s lower than the clip.

Click to view attachment

When I did mine, the glass also sat too low with the thinner rubber spacers. I doubled them so the glass sat more centered top to bottom.

You don't want the glass resting on the clip. The clip needs to flex a little to allow the molding to snap into place. The glass can slide down too far without an appropriate spacer. I don't really like the spacer you've got.

I believe that dimension is detailed within this manual-(Chassis). IIRC this gives the exact dimensions and IIRC the material is wood. You could mill them from plasticI suppose. I threw away the rubber strips and used wood pieces from a yardstick. http://p914-6info.net/PDFs/Group%208%20Body.pdf