tangled seat belts??

Now maybe I am a total idiot BUT,how do you fix tangled seat belts?I've had two mechanics tell me two different things.One included battery disconnection,fuse pulling,removal of lower retractor twisting and re-installing,all very carefully as if something was going to explode or something.The second mechanic told me " just pop out the upper {shoulder} connection,twist it straight,and put it back" I looked up the latter in the manual and it said simply"step 1,remove upper panel,but neglected to say how to remove upper retractor panel .As I browse the instructions for many repair procedures,I see this a lot.It will say remove something,but not how to remove it. Am I missing some great point,or should I not even try anything until I complete a BMW repair tech school??
Again,I am laughing while I say this,I am 62 years old,and believe it or not,have repaired my own cars on most of my life.Growing up in the 60s and 70s ,one had to work on cars just to keep them running.So maybe it is time for me to get a 50s or 60s car again!!!!!