The easiest way to remove windows from a Ford F-1 truck from '40-'47 is to first remove the inside door handle by pressing-back the escution and tapping the pin holding the handle and spring-loaded escution on the shaft. This will allow you to remove the screws and door plate. You will see the window regulator mechanism in front of you. CAREFULLY remove the nut and bolt that goes through the assembly, and between the regulator gears. This seems illogical, but is the item that testrains the arms traveling in the guide, from indexing too far and letting the window free from the regulator. That's exactly what you need to be able to turn the window 90 degrees and be slowly removed from the door. Keep this nut and bolt as it will be needed when reassembling the new window into the regulator. You will need to crank the regulator to the point where you can start the regulator arms into the track and raise the window up some. When you can get the bolt back into the regulator, insert it and thread the nut back onto the bolt and tighten it. The window should work as before. It is adviseable to replace window guides and felts before this, but the truth is the felts may have to be replaced after the window is inside the door, but below the normal position. Replace the door panel and window crank assembly, and the job is done!