You didn't buy a lemon, you bought an old truck. All of them are ongoing projects passed from one person to another. This is what you take on as an owner. This is what Stovebolt is for. To turn you into a mechanic of sorts, provided you enjoy the "hobby". All of our newer vehicles will have problems from time to time also. The difference is that these old trucks are much simpler. Usually "easy" and cheap to fix. You will get used to figuring out things and getting them handled. We can help most times. Some people are lucky enough to have all the work done by a shop. Wealthy enough to have the whole truck completely restored by someone. Not too many come to Stovebolt. Even if you have never worked on cars and trucks, the simple, old school, practical, well designed trucks covered here are the best ones to learn on. It's never too late to catch the bug.
Once you get the starter figured out, you go to the next thing. No rush. If it starts to get you down ,or too annoying, or to intimidating, then it's time to sell it. It's not your bag.
As far as your transmission goes, it is cheaper and faster to find a complete transmission, put in a new clutch and throw out bearing and move on. Not a good idea to rebuild or have it rebuilt. Too many good donors out there. That's a later discussion for another new post.
Plenty of experienced members here. Some were actual automotive instructors like Hot Rod Jerry. Good stuff. Practical DIY fixes. Other methods like buying new parts sometimes or having a mechanic fix something, is absolutely kosher if you can't do it. Might be one of Jerry's students from 90 years ago.