Howdy Chaz:
I just had to add a few more observations.
Bolting in a Pertonix is easier. But will only be as good as the distributor you mount it in. At least upgrade to a '68 distributor that has Centrifugal advance along with vacuum. And make sure the host distributor mechanisms are in good working order.
The flame thrower coil, all be itself, is a good addition, and will even improve the performance of a stock distributor. It will likely be harder on points if you open the plug gap to take advantage of the hotter spark.
All of the DSII distributors I've used came from the junk yard. I've never paid more than $20.00 for the whole works. "Whole Works" means complete distributor, plug wires, coil, wiring harness, and module. The only thing to check is the tighness of the shaft in the distributor housing- up and down and side to side. Pass if it is either too loose or too tight. Other than that, clean the system up, install and enjoy. Only parts to wear are the cap and rotor. I've only had one module ever quit on me. They either work or they don't, so it is a good idea to have a spare handy.
So far, I've only used the stock DSII coil and stock module.
The DSII requires just a bit more mechanical and wiring than the Pertonix.
PetroniX is the way to go for stock appearing.
Both require fine tuning to get the most out of them with your system.
That's my 2 cents.
Adios, David