Wow, now that's the right way to get a head job. Ok retake, the new clutch is a must. The timing I would definitly get and the ARP bolts still aren't completely neccesary but are still prefered over stock in this situation. I'd also think of getting a stronger and/or thinner head gasket. The nitrous? I don't think your stock bottom end could take the new found head WITH an additional 50 shot of "NAWS". I'd atleast get some stronger rods before trying. It sounds like you've designed this with natural aspiration in mind. Some new forged and/or higher compression pistons would be right up your alley but they might bump up the compression to the point where other things might need to be upgraded as well. You'll at the very least need to invest in a savings account to save up for a life of 93 octane.