My 87 G20, the front passenger side door decided not to open anymore. There was no sign that anything was wrong with it previously, just went out this morning and it doesn't open. The lock also won't pull all the way up, it springs back down. How might I go about fixing this without damaging anything else? Also, my side door is a slider. It has a little bit of trouble closing sometimes. If I don't get it just right, I have to give the back end of the door a little shoulder bump before I can put the latch fully down. I think it's a problem with the roller/track. Not sure how to go about tweaking it.