Amazing, a guy on Mirafiori asked the exact same question, so here's what I told him!
With a new regulator, it should have a little temporary metal clip near the drum that keeps the cable from unwinding, but if it doesn't, you can wrap the two "ends" of the cable coming off the drum with a bit of masking tape or the like, once you have the cable wound correctly around the drum. Once the cable is installed, you remove the clip or the tape of course.
The other thing to remember is that the cables come off the drum in a sort of counterintuitive way. Coming off the bottom of the regulator drum, the cable routes towards the inside of the car, then up to the top front pulley near the window sill, then down to the lower front pulley on the bracket, then back up diagonally to the top rear pulley, then down to the lower rear pulley on the bracket, then frontwards past the adjustable pulley, then to the top of the drum on the outside of the other segment of the cable (where it started).
Before starting, loosen the adjustable pulley and push it towards the rear of the car as far as it will go Also, under the door frame, loosen the two bolts that hold that bottom bracket. Not fully loose, but just enough so that the bracket can move up and down a bit. Makes the cable easier to install.
After the cable is routed, it's just a matter of adjustment to getting the cable adjusted. While it might seem like the cable should be really taut, I have found it works best with a bit of slack. Not enough to jump off a pulley of course.
Also, the cable will have to routed through the two bolt/nut "clamps" that hold the cable to the bottom of the window, and how the cable is positioned on those clamps relative to each other will determine whether the window goes up and down in the channel as it should, or tends to get cocked.
There's a lot more in terms of adjustment, but in the interest of time, I'll leave it at that. Let me know if you want pointers on anything else.
Hope this makes sense...!
-Bryan
arrrgh!
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