Installing small front of window guides in 1966 Monaco 500 – help!

I just purchased the parts to replace the front window guides on my 1966 Monaco 500 hardtop with power windows
Can someone give me pointers on how to install these?
I've seen some videos that indicate there is a screw at the top, I don't see any screw at the top.
Do I have to remove the entire wind wing assembly?
Should I purchase new bottom window mount pieces?
I figure that I won't be able to take them apart after 57 years they won't be re-usable.
All advice is welcome
Thanks
Scott