Something (sticky transom shift cable) is holding your ESA engaged. It should be RIGHT in the middle. As a test you can temporarily disconnect the shift cable at the point where its held in with the cotter pin on each end that should allow the load lever (grey part with the V notch) to relax so the trigger arm for the ESA rests in the middle.
If you read the "adults only" section you will find the part that explains how points and condenser ignition works. Its not hard but setting the point gap can be a fiddly pain. I learned back in the early '70s on a 1965 VW Beetle 1200 cc 40 hp. Then graduated to a Delco window distributor on our '72 Chevrolet 350. Also did a '70 Ford with an Autolite distributor. So the boat distributor is easy for me. Have you tested for spark yet? Get a spare spark plug. Make up a ground wire with a pair of alligator clips. Clip one end on the threads of the plug and the other on clean engine ground. Disconnect one of the plug wires on the engine and plug it into your spare plug and look at the gap between the side and center electrodes when someone cranks the engine. Should see a nice bright bluish-white spark. If you see this then the distributor is not likely your problem. Back to the Holley carb. Have you looked at
www.holley.com? Time to get educated in '70s auto tech. Its really quite simple. Got any older dudes around your neighborhood who are good with a wrench? What you got is ultra simple...points distributor....Holley carb....like any Ford...of 60 years ago lol.
Always check for and verify proper spark first...then if that's ok...move on to the fuel system.
Are you in the UK? If so find an old car club, with a few Ford Cortina or Ford Capri guys....they will know....
time to start reading:
https://forums.iboats.com/forum/eng...roubleshoot-a-points-ignition-system?t=335407
some Cobra drive information here good for you to know...
https://forums.iboats.com/forum/eng...nes-outdrives/342742-omc-information?t=334348