No reason you cant do it yourself, Imo you should get head reworked by a machine shop ( new guides etc) have the engine and crank checked.
If you are doing a full rebuild and depending on mile history etc I would use new pistons and uprated oil pump. use all genuine bearings etc
Make sure you keep everything clean from dust, dirt etc, and dont skimp on the running in process,
Sounds like alot of time and money, well it is, but if it needs to be done do it right, once and you will still save alot of money

Oh and dont forget if your not sure about something, Ask the question