My seatbelts in my '00 v-6 mustang will get "stretched" and won't slide back into the holder. It's because it gets tangled from what my dad believes is a factory defect of putting them in backwards.

My car also has a loose driver side panel where your power window switches are, but after looking at other cars in my body style around town, it's a common problem of them getting pulled out.
So i'm wondering, is this seatbelt issue an isolated one, or has anyone else experienced it even with other body styles?  

Do you have the guide by the head rest or not? I found without the guide it goes back good till it gets near the end. If I take it out of the guide then the last bit is like slow movin.