Wow! Great write up!!!!
But, a couple of things: the 7 wire module, 7th wire is a ground. I installed one of these systems in my 74 Cougar with the 351C. Worked great! Could never get my Edelbrock water injection system to work with it though! I was gonna look some of what you wrote up in the books,, but found I must have sold them! No longer on the shelf! They've been replaced with 1979 books, which indeed cover the DS-II system in great depth.
#2 Correct. Internal coil resistance values are different between DS-II and points type.
#3 Coil must be vertical???? I beg to differ and will be taking notes the next time I find a DSII equipped truck or station wagon. I believe that Ford used the same "lay down" coil bracket that came out in the 60's for SBF's, to mount the coil on the intake manifold on all engines up to the 460's in trucks.
#6 If you are running a resistor wire already, you do not need a ballast resistor. In fact, I believe you can even run this DS-II system without a resistor wire or a ballast resistor. This is why I chose it for my Goose. DeT never used a resistor wire....and I was boiling my old coils until I found out about this!!!! Changing to the DS-II system resolved that issue!
Your drawing shows an additional relay installed, which really is not necessary in most all cases when retrofitting into a Ford. I've never seen this in the Ford books or articles on the topic....yet.
#7 Spark scatter: I believe this is why Ford went to the larger distributor cap setup. To help prevent the cross firing.
Distributor wearing out at 50K???? Knowing that the parts books show the same identical bushing for almost every distributor made since the early 60's (Ford MPC...look it up.), why would a breakerless distributor wear any faster than one with points???? That doesn't make sense....unless your sources were talking about the pickup modules failing. I have had these fail, but only perhaps once in 16 years since installation in a daily driven car (and it was used already...).
If you look at your distributor body part number, it will be a C9ZZ....casting number. It is sourced from a 1969 351W distributor! Yes, you to can run a Windsor distributor in your 351C by simply changing the distributor gear.
Sorry, just can't buy the 50K wear out thing. That would imply that every 351W car still running out there today is doing so with a bad distributor.....
Now, perhaps if we're talking about worn out advance pivots, or advance bushings, that may be something that was skimped on in later years..... If you have any concerns, grab a 69-73 351W or 351C distributor and convert it over to a Duraspark unit by swapping in the breaker plate etc. You need to plug the old round hole for the wire, and cut a slot for the new wiring of the pickup module, but no big deal! This is not rocket science.
The thing about shocking yourself is true. Do not "knock" on the distributor if the rotor is lined up with the pickup, and the ignition switch is on.... In fact that is how you can test them!!! Just tap the distributor with a screwdriver head or similar and you'll get a spark! Comes in handy from time to time!
Since the availability of DS-1 modules is sketchy at best in terms of picking one up in the middle of no-where.....I would still advocate the DS-II module. Blue strain relief.
As for other colors, popular myth and junk yard observations would indicate that they are sorta keyed towards number of cylinders.... probably different advance/retard function to better fit the engine class....but, I have never found any documentation to support this. As far as a module goes, it DOES NOT CARE if an 8 cylinder distributor is telling it to fire, or a two cylinder pickup is telling it to fire.....so if you needed a new module, you could really get down the road on anything that a parts vendor or side of the road-kill donor could provide!
Ciao!
Steve