My window lowers fine,but only goes 3/4 up. I assumed regulator. While waiting on it to arrive I removed the door panel. I then attempted to remove the inner metal panel. It seems there are rivets holding it to the glass. Do they need to be drilled out, and if so, once the regulator is replaced what do you replace them with? It's not a standard size rivet so I'm at a loss. I've been all over the forums,YouTube and Google, but nothing mentions anything about it. Any ideas are appreciated. I'm new to water cooled vws and I'm soaking in everything I can.