Try watching some you tube videos. I like using a pencil eraser and alcohol instead of a screwdriver to clean the contacts. Also a slight film of dielectric grease on the contacts will make it last longer. https://www.youtube.com/results?search_query=silverado+window+switch+repair
There is a five dollar screen under the oil pressure sender. You tube has several videos on how to change it. The screen is to filter the oil to the DOD lifters. It gets cruddy and soon drops the oil pressure. I took mine out and ran the engine for a second to flush the oil gallery before I put in the new screen.