Excellent
guide.
Just a thought. If the pipe normally comes off the back of the wiper motor, would it be possible, while the trim is off, to cut a hole – say 50mm – in line with the motor and fit a blanking grommit to allow access for a pair of long nosed pliers if the pipe were to come off again. I suppose it wouldn't
help if the pipe separates anywhere else but it is just an idea to save having to keep removing the trim.