Low idle, and misfire. Thoughts before I buy a timing gun...

Hello all,

Before I go out and buy a timing gun, I was hoping to hear your thoughts on this short video clip. Finally got my 76 280z running and idling after finding a vacuum leak at the booster, but the idle is still really low, and I believe I hear it missing/bogging when accelerating ? idle adjustment screw seems to do nothing in either direction. New plugs, new plug wires, new water temp sensor, new battery, cleaned the injector plug connections, but that's about it. 

Thank you,

Oscar