It does seem pretty overwhelming, first time building an engine, not a lot of knowledge or know how, or tools, or space... or money............
ANYWAY, we all had to start somewhere. I started out like you, no cash, nothing but limited book knowledge about the basic principles of building a V8. It will all come to you in time. Just take a step back, get a fresh notebook, and write out every thing you think you need to get the 305 out, and a 350 and a TH350 in. Fill up the whole book if you have too. There's plenty of people that have done this 100 times over on here willing to help. In the mean time, look at replacing stuff like brake components, shocks, rubber bushings, stuff like that to make the car safe with almost twice the power you have now. Of course, if the car only has 22k, just inspect the parts, replace as needed, and grease everything you can.