Thanks for adding info and pictures. Bisbee is going to need some lovin', but I think not near as much as many do. If you don't already have your hands on a shop manual, or parts manuals for that matter, check out the many free to use linked resources at
Keith Hardy's Old Online Chevy Manuals.
You'll find the 1948-51 Chevy Truck Shop Manual to help you get started on the various stock aspects of your project. Between these resources and asking questions in the most on-topic forum for what you are working on, folks will gladly offer their experience and tales of trials and tribulations on their trucks to help you work on yours.
You will also find that other folks have done the swap to the later style 6 cylinder, so if you are skeptical of your current setup, you can show us what you have and ask for help in figuring out what to do/not do in that department.
