it can be done, you will need the door cards complete with switches from the old van, the door wiring looms complete, and the window motors, basically everything out the doors except the speakers, door lock motor, glass, and glass side runners. everything else will need to be swapped for one to the other.
Took me about 30 minutes to do both sides on mine, but I'm used to working on transits
remove door card (screws down both sides and bottom, inside door handle, inside door lock release handle, and remove window winder which just pulls off) in lip door panel and lift off. peel away plastic covering film underneath, unclimbed and unplug all door wiring then remove the connection from he van body to the door by turning the round part about half a turn. remove the loom from the door by pulling the rubber boot section out of the door and feeding all the loom through (yes it must all go that way)
temporarily re attach window winder handle, and lower window until two bolts are accessible at the bottom edge of the glass. remove handle, remove those bolts.remove the outer window guide / runner from inside the door (held in with bolts) Pull the rubber window seal / surround out around the glass opening, and up out of the door then slide the glass up and out towards the outside (it does fit, but only in one position), remove the winder support bolts (x3) and the central glass guide runner (nuts at top and bottom if I recall correctly). remove complete winder assembly,
replace with new bits in reverse order, don't forget the one touch relay module to bolt onto the drivers door at the bottom left corner and plug into the loom. Fit fuse to dash fuse box and hope all the rest of the loom is there inside the van
If vans are the same colour, you could also just swap the doors complete instead
Andy