Just got a gtp help me with a few small problems please

[War97gtp]

Hi everyone I just bought a 97 gtp today with 43k miles. There are a few minor issues. Problem #1: The drivers door power window gets stuck at about 6 inches from the top when going up and if I push the window glass towards the back of the car it will go up the rest of the way. What could be causing this a bad regulator perhaps? what would the fix be for this. #2: I hear some pretty loud popping noises every once in a while coming from what sounds like one or both of the rear speakers. Could this be the factory amp that is bad? (I ordered a new headunit because the car only has a cassette player maybe this will fix it?) #3: The HUD wont move up or down if I try to adjust it otherwise it works fine. Would this be the switch or something in the HUD unit.
Any help is appreciated.

[Sven the Sexman]

1. Bad regulator
2. Replace all stock/Monsoon crap with aftermarket
3. Need to reinstall the spring on the HUD more than likely

[War97gtp]

Thanks I got a new regulator on the way, I hope its not too hard to change. I was driving around all day today (sunny and dry) and there was no more popping noises coming from the rear speakers. It was making the noise while driving around in heavy rain yesterday maybe that has something to do with it.
How do I check/reinstall the spring on the HUD.