Where does one start?

[Diablo de la Noche]

I want to fix this truck up, but also want to enjoy it as long as possible. Where do I start? I know I have to go through every square inch of it and probably replace most of the soft stuff. Its a 67 longbed with almost no rust. I got it started at the dealer (yes, the dealer) and it scared me. the engine is a chevy 350 and is really untamed. I had it towed to my house because they said it was unsafe to drive on the highway. Now, why did I buy an unsafe vehicle from a dealer? Because it is a 67 GMC longbed with no rust and was only $900.
So, no rust, no straight panels but no real kinks, solid underneath, scary 350, and nothing works right. It does run and drive and I want to enjoy it. It won't be a resto because I don't want to put in the original v-6 and the numbers won't match anyway. It will be a mild custom. Where do I start?