I scanned it from the Mopar Performance instructions DCF- 194 that came with their conversion kit with the Chrysler built distributor.
That's exactly it. Even if it was true that only Chrysler-Plymouth used ported vacuum, that doesn't prove anything. We're dealing with a Chrysler.
Yes I can point to actual examples of engines that used manifold vacuum for the distributor. I know you can too.
We also know the OP is not working on a 1964 Kaiser Jeep OHC 6 cylinder or any of the other examples.
Further its not even true that all other car companies only used manifold vacuum pre-emissions.
I've also pointed to examples from
1964-65 where Chevrolet's used ported vacuum.
Shrinker mentions a 1949 Jewett he owned that used ported.
Then there was the Ford system that used venturi vacuum - a totally different way of matching timing to engine rpm and load.
Almost every different engine combo has somewhat different timing needs. The combustion chambers, the piston dwell time around TDC, etc etc. all have some effect on the burn, and therefore the lead time needed under different conditions.
To the best of our knowledge
@dartfreak75 has a fairly stock Chrysler engine with a Chrysler distributor.
However until we see a full set of actual timing-rpm measurements all of these sidetracks are just theoretical distractions.