Crappy Electric Windows

Does anyone know if it is possible to replace the electric windows (which have never worked twice in a row) on my Defender (2002) with manual ones? Would I need to buy the metal 'scissor' gadget as well as handles/clip or what? On the driver's side the fuse pops every time I use it and two mechanics have tried in vain to repair broken wires, which I suppose is the cause of the fusing. On the passenger's side it is a different issue. It seems to come off it's runners and go lopsided and won't go up, but the fuse is fine and the motor works (I can only imagine the scissor thing is probably buckled as it seems to be a weak piece of crap from what I've seen on various youtube clips!) The passenger window is currently held up with silage tape which is incredibly sticky and strong!! Any suggestions would be greatly appreciated. I'm living in County Kerry and Land Rover mechanics are few and far between. Is it a job I can do myself or not do you think? (I'm reasonably capable at mechanical things but more comfortable with sheep!) Anyway, thanks for reading, and Happy New Year

The doors tend to go out of shape and this in turn causes the regulator and runners to run out of alignment, allowing the glass to come out of the channel. Fitting a manual regulator wouldn't fix this issue. As for the wiring fault with the other side, there's not a lot to it and it certainly doesn't need a Land Rover mechanic to diagnose a fault. If your local garage options are limited (or breed of mechanic perhaps) you may get better results by learning how to diagnose electrical faults yourself and it will be useful to you for years to come.

Take the door card off, either the guide on the bottom of the glass has broke/fell off/rusted or...
The guides running either side of the glass have failed simlairy...or
The scissor is bust.
Not too dear to fix but can be a ballache with rusty screws and the like.
Wiring fault is probably in the rubber franger that carries the wires or close to that, the wires bend every time the door is opened and closed and can break.