To put your mind at ease plus learn something I would suggest that you start with a good "old fashioned brake job". It's not that difficult to do and you would clearly understand how everything works in your truck's brake system. When your done you will be most confident that you can "STOP" your truck!! Safety concern Number 1!!
Just by dissassembling all the brake parts, cleaning them, installing new wheel cylinder kits after honing the wheel cylinders, checking the drums to make sure there not scarred (if so they may need to be turned on a lathe), inspecting the brake shoes for wear to see if you need to replace any of them (in pairs mind you), and finally topping off the whole system with fresh brake fluid and bleeding the system of air bubbles....you should be in good shape!! Just approach all these tasks methodically, with patients taking your time to do a good job. If you get hung up or have a concern you know that there are plenty of folks here that are more than happy to guide you through! I didn't mention "ALL" the steps you must take so be prepared to ask questions!
And, BTW, take some pictures with that camera as you work! For documentation on how the parts fit so that you will remember just how they go back together! Most of all, don't be afraid!! You can't mess up. It's only a bunch of parts!!
