BEFORE you start ordering parts, pull off the door panel and look inside and then activate the window and figure out what the problem is....on one end of the "regulator arm" there's a toggle that fits into a track along the bottom of the window to move the window up/down so you might try and grease the toggle and track and see if the toggle is binding or broken and the other end of the regulator arm has teeth that mate with the pw motor gear at the power source.
Look at the door "felt tracks" that the window slides up/down it's really the anti-rattle device and over time they get loose and broken possibly binding the window where you might need to replace them.
www.lmctruck.com or
www.denniscarpenterauto.com usually has them.....
Power window motors can be rebuilt with kits that are not expensive rather then buy an "aftermarket" that might not fit properly so keep the OEM original for that reason. The motors are "torque pin riveted" to the sheetmetal inside so you need to drill out the pins in order to remove the motor for repair but using small grade 8 bolts with heat shrink on the blank part of the bolts will work to make a tight fit thru the pw motor mounting holes. If you can't rebuild it yourself then take it to an Auto Electirc Shop to do it for you.
The "regulator arm" pivots on a short round stud in the middle and fits in a hole in the sheetmetal so make sure it's sitting in there properly so it see saws correctly, any iusse with the regulator arm will make it pull out away from the pivot hole affecting the window's movement.
The tailgate is another animal but has similar issues like door windows, if you can get the window down below the top level of the TG box or weather strip area the handle will "clear" and you'll be able to drop the tailgate.
Check that the TG "closes flush" with the body line otherwise the safety switch inside will prevent the window from working. Using a T-50 Torx socket you can either loosen the "door striker bolt" and adjust it inward or completely unscrew the bolt to replace the "door striker bushing" anti-rattle device using some lubricant to help slide the bushing on the bolt shaft.
Both Door/TG Striker parts (Doorman mfg.) are available in the Help section of most auto stores Bolts #38420 - $7.99 each and Bushings # 38424 -$3.99 4 pack.
Also when you have the TG down look in the left rear quarter panel for the wiring harness that goes to the pw motor, over time it gets bent and damaged from opening & closing the TG possibly affecting voltage to the motor.
There plenty more TG info so check out FSB member Steve83's "tailgate tech" album by clicking on his black Bronco.
Good Luck ~ :thumbup
