Down the rabbit whole again... King Cobra Spit fire

Evening yall, So I once again bought another classic boat. 91 Ski Sanger King Cobra 350/OMC ( Miami Vice). Yesterday we decided to take it on on a test rip, everything was great, Shut her off to test a hot restart and failed immediately. ( I had a funny feeling) Let it cool down and fired off again, Checked all the Basics on the water, Fuel, breakers and spark. Found that when it got hot there was no spark.
After a few hours of researching the issue this morning, i guess its a pretty common issue with these spitfire ignition setup. Did the research on a EST swap https://marinepartssource.com/delco-est-conversion-kit-v8-sierra-18-5514

Ending up buying it, My question is, is there anything else that i need to make this kit work? From my understanding its pretty much plug and play. Any advice is more the welcomed. Anything else i should besides this? Already found a good amount of parts for the OMC outdrive. I absolutely love the older boats,

I would like to update the coil to a heavier one? I'm a heavy diesel mechanic, not a gasser mechanic. I know the basic but some of this older stuff is beyond me.

You may need a new ESA module that will work with the electronic ignition, or else you won't be able to shift it to neutral when you have it in the water and there's a load on the prop. Call CDI electronics and tell them what you're doing and they should be able to suggest one of the ones they make.
What the ESA module does, is it lowers the engine idle when the linkage senses a load on the shift cable, that should drop the idle from 600 rpm to 450 rpm, and then you can get the gear shift into neutral. If it's not working it will be very difficult to shift to neutral, which can be dangerous on the water.