Transmissions for dummies?

[ahoke]

Thanks for the responses, fellas. I am totally onboard with keeping it stock, just making sure I do not have unrealistic expectations or unnecessary wear that will soon become a bigger issue after putting time into it.

Back story if anyone is interested: Picked up a '72 C20 last summer and have had a blast with it, even taking it to cut some loads of firewood. But I do not have a history or experience with working on vehicles. Sent my buddy a video of an oil leak shortly after buying it, and he suggested replacing the front seal. Next thing I know I am dropping the oil pan. (Again, no experience so I didn't know what a water pump was until I took a bolt out and antifreeze starting pouring out.) Wanted to know more about fixing these trucks and sought out an engine to rebuild myself. After not long on the classifieds it seemed smarter to just find another truck that needed the engine rebuilt. Found my 1970 C25 tucked away in a barn since 1998, no rust. Even has a dump bed on it.
Next project is to pull the engine and transmission (bought an overhaul kit for the TH350 that I'll be using).