I know this is an old thread, but im sure more and more owners are getting drowned motors. After 5 years-yes 5 years of my roof not working have confirmed that it is definitely the motor. I have now taken early retirement and am looking to keep busy, So yesterday I attempted to remove the motor without taking the roof off. After 5 hours of tinkering(on and off - it would be impossible to remain working in the boot for this length of time)
I managed to get it out. Having done the job once I reckon I could now do it in less than an hour.I can now see that you could adopt a couple of different ways of making a quicker and much easier removal
So its not impossible and not as difficult as you may think. And a whole lot better than removing the roof. Huge satisfaction when I had the motor in my hand in the boot