I have been noticing my drivers side wiper has been skipping across the windshield lately so right away first thing that came to mind was replace the wiper blade, since that didn't work and its starting to get cold I really need to figure this out.

I tightened up the nut on the arm but there is play below the plastic shield under the wiper arm and I can't find anything anywhere to give me an idea if its a hearing or something in the wiper motor itself or some linkage that needs replacing so I figured I'd turn here for some ideas and hopefully figure out how the hell I'm supposed to get those plastic screws out for the shield under the wiper arm since they just seem to spin in place

 

I had to put some washers on my hinges a couple of days ago.Both ends of the cowl covers had to be removed.I thought that they where steel at first but wasn`t.They just kept spinning like yours are doing.The ones I was dealing with where easy to get to.So I just pryed them off with a small molding tool.I don`t know why GM would use plastic screws.But in your case.You may have to try and spin the screw and pull up at the same time with a flat head style pliers.Looks like needle nose pliers,but it has a flat tips on it.You don`t want to break the cowl covers at all, unless you want to spend about $200.00 for new ones from LMC Truck.I just broke the screws off and bought new plastic retainers and screws.From LMC truck,It cost $12.00 for 2 screws, 2 plastic retainers.When they get to my house..I`m gonna try and use stainless steel screws instead of the plastic ones.