I recommend the Pertronix as well. Derek and I are running one on our '72 and it works very well. After we installed it, the motor was much smoother and had more zip. It doesn't really add horsepower persay, just more spunk. It's also good for higher revs, unlike the original points.
Yeah i'm not expecting a hp boost, but i'm hoping to get rid of the backfires and have a better start and idle. This along with the carb tuneup should do her, and the pertronix is cheap enough. How about the install and adjustment? Was that easy?
I'm running the Ignitor as well on my 240z. Rather simple install. I also bought the Pertronix Coil for around $28. Lot easier to deal with then points. Search the archives there is a place called Retro Rockets that sells the Ignitor new for $65. http://www.vintageperformance.com/retrorockets/index.html Only major discussion I've seen about the Ignitor is over using the ballast resistors w/ stock coil. Since I'm also using the Pertronix Coil, I removed the ballast resistor.