New Member With 1962 C10

[C14V]

Hey guys I'm a new member here. I'm Carlos. 19 years old. Live in Arizona. And I have a 1962 C10. The truck was given to me by my grandfather. He's had it sitting for a while and he knew I had been wanting it and he finally decided to give it to me. I've had it for maybe 3 months, so I'm still learning stuff about it but I have already replaced a couple parts since it has been sitting for a good while before it was given to me. The truck did have a standard transmission and a different engine but it was all swapped out. They put a 350 in it (idk from what- or even what year it is). Put in a automatic transmission. I'm also not sure which tranny. All I remember is that my grandpa told me the transmission was ??400 so maybe one of you guys can help me out. I dont much about engines and transmissions just enough to get me by but I'm always looking to learn. I want to know what should I change soon, what are better mods for CSB etc.. I want to change the radiatior soon since it has a small crack in it near the top. But idk where to get a good radiator that will keep my SBC at a good temp. I live in the sunniest city so the truck tends to get hot but as long as it has water in the radiator and overflow I'm golden. Thanks guys! looking forward to learning!

Here are some pics.