I haven't done my 41 yet, but I have the glass on order and the guy walked me through it on the phone. The 41 and 47 are very similar.
Obviously, you have to take out the old glass, regulator, vent wing assembly, and vent wing regulator. You have to take out the front channel/adjuster. You have to cut open the area that was originally under the vent wing. Modify the channel/adjuster so that it will attach to the very front of the window opening. You will have to locate and drill a hole for the lower attachment/adjusting screw. If you are using the stock regulator, you will have to weld a piece of 3/16" rod bent into an "L" shape to the front of it. You want the short leg of the "L" to ride in the front channel to give the glass extra stability going up and down. If you are using power windows, you may or may not have to do the "L" extension. Now for the fun part. If you sight down the bottom of the window as it is now, you will notice that the door has a "jog" in the opening right where the window ends and the vent wing begins. You will have to form and weld a piece of sheet metal to make this closer to a straight line. The guy I am buying the glass from indicate a piece 8 - 10 inches long would do the job. Likewise, you have to modify the interior garnish buy cutting a wedge out of it or bending it. Glue in channel attach the cat whiskers (or whatever you call them). I am not looking forward to the body work cause I'm not that great at it and I am slow. But the ones I have seen really look a lot cleaner, so I think it will be worth it.