Gary,
Here is a great filmstrip capture that may help. There is a lot you can do with the originals with some work. Drivers side is usually much worse due to use, careful alignment, some simple relatively cheap replacement parts can usually get them to stay closed until a complete rebuild or alternatives are sourced. I hate to see you miss out on enjoying your truck now it is spring!
https://www.flickr.com/photos/advance-design_parts_co/sets/72157641244124604/
