Augusto - Originally, I put the Duraspark II triggger assembly in the distributor of my Thunderbird and rigged it to run with the "blue" module. The best one I found was made by "Standard" - but it wouldn't handle a coil with a low OHM primary winding. Total primary plus the ballast had to be over 1.6 OHMs. So....I built this replacement that uses the GM four pin module and plugs into the Ford harness connectors...bolts in the same spot.
It doesn't have the 6° starting retard of the Ford style unit - but will handle some really powerful coils (low primary OHMs) without a ballast resistor. It will run a TFI type coil virtually forever. I wanted a hotter coil - factory type part - so I wasn't paying for a "name brand" - and found the GM "E-core" from a small V6 pickup worked like a charm. it is roughly .5 OHMs primary.
If you hook up an old fashioned "dwell meter" to this outfit, you will find that the HEI module drives the dwell down to about 15° at idle (keeps the coil AMPs and heat down) - and then jacks it up to over 35° at elevated RPM. So it is similar in dwell to an old dual point distributor at the high end - but can use a modern coil with way more jolt than points could ever tolerate. The GM replacement coil shown here has the same operating specs as an MSD "StreetFire" E-core coil - you can get them brand new from the internet for about $10/$15 - and less at the salvage yard.