It is almost impossible to say without knowing you personally. I built my first engine (SBC 350) when I was 18. All I did was read "How to Build Your Small Block Chevy" and I had no problems. Engine rebuild went fairly well and the engine ran strong.
If you've never been "deep" in an engine before (ie.. dropped a crank, pulled a piston, installed a timing chain, installed an oil pump..etc.), you may want to have someone around who has built an engine or two to give you a hand. However, if you feel pretty confident about your mechanical ability you can probably swing it with a good "rebuild manual" or two.
BTW.. that engine sounds pretty bad