I installed pwr windows in my truck some time back with issues. Always had a plan to get back to it & fix my mistakes. When I originally did the install I used the track on my windows which was the beginning of my mistake. The next thing I did wrong was I set the regulator at halfway & mounted based on that with the window halfway up. The track on the bump windows is narrower & shorter. The original track is still on the window in this picture with the F150 track laying on the window just above it
This required grinding the nylon down on the end of the '90 F150 regulators so that it would fit.
This is what the nylon looks like when in the F150.
We start by removing the door panel. I assume most all know how to do that.
You will notice a screw located just above the door panel. This screw is part of what hold the vent window in. You will also notice I have a hole in my door panel. That is where the crank was. In this next image we see 3 screws running up the front of the door. These too help hold the vent window in place.
In this picture you will see I have made 2 cuts in the door to remove the recessed areas. They are in the way of the regulator movement. Just below the regulator gear you see a nut. That is the final piece that holds the vent window in place.
Since we will be changing the track we need to remove the vent window in order to remove the main glass. Once it is removed either you can change the track or you can take it to a local glass shop & they will do it for you. I was going to do mine but the rubber was so far deteriorated I ended up taking it to a glass shop. It cost $10 to have them put it together with new rubber. A great investment in my opinion. Here is the window with the track removed.
Here is the window after I got it back from the glass shop.
You will notice in the picture of the door with the panel removed 3 shiny nuts. Those are what was holding the regulator in place. What you want to do is set the regulator in the all the way down position. At this point when laced into the track You will be able to line up one of the holes with the lower right original regulator hole. You will also notice that the window travels upward through the door on an angle. You want to set the regulator up to match this angle of travel as best as you can. This reduces stress on all the pieces involved. I used 1/4" flat washers that I glued together. In this lower right corner I used 9 washers. I had to move slightly to the left of my original holes from the 1st attempt. In the top right I used 5 washers & top left I used 7. I used a small tie wrap laced through the washers to lower them in place without losing them in the bottom of the door. It worked well.
You major issue in doing this is the hinge mounts at the front of the door but spacing the regulator out to match travel path allows the regulator to clear with no interference. This is a great mod in my opinion that can be accomplished with factory parts. Cost to accomplish is minimal. Regulator with motor & track from Pull A Part is $20.xx per door. Not sure what switches & the harness would cost but I am betting you will come in under $75. Any future problems & you are using off the shelf Ford parts that you can get at any parts store.