I have the Pertronix IgnitorIII distributor in my BB low deck with Eddy heads, it was a nightmare getting the distributor to clear the head but it's been in there for a few months and runs perfect.

I don't like the rev limiter, it kicks in 800 RPM too early so I had to set it higher, and it is hard to set, you have to mess with the little screwdriver knob forever to find the setting you want. I'm considering buying the Pertronix600 rev limit box, it's about $135 but the settings are much easier to do and with it being hardwired into the car I would hope it would be more accurate.

I installed a Raptor shift light also and my tachometer matches the shift light perfectly so I don't think it's my tach.