This is an interesting way to restart a dead thread.
Shortly after I wrote this thread, my motor rebuild project was put on hold... for several years. I had decided to move onto another part of the project and went to rebuild the lower unit. When I tried to remove the powerhead to access the impeller, one of the bolts was seized and I couldn't free it. So I mothballed the whole thing and it sat in my garage gathering dust.
Fast forward to a month ago. I have since graduated college and begun my career in engineering. I have learned a little bit more about working with tools and decided to revisit this project. I attacked the seized bolt and ended up have to drill out and re-tap the hole. Spurred on by my small success, I kept at it and am proud to say that I have made serious progress.
This is still the first and only engine I've ever attempted to rebuild. As of today I have:
*completely cleaned and rebuilt the pressure fuel tank, modifying it to function as a standard single line tank (I replaced all the line with new fuel line, new connectors and a new primer bulb, and I replaced the fuel and oil)
*completely cleaned and rebuilt the carburetor with all new components from a rebuild kit (soaked all the parts in carb cleaner overnight and blew them out with compressed air)
*cleaned the combustion chambers and installed a new head gasket
*cleaned and rebuilt the lower unit impeller and replaced the hypoid gear oil
*replaced all fuel lines and installed a brand new Mikuni fuel pump after removing the check valve from the intake manifold and plugging up one of the holes
*I also replaced the coils, points, condensers, spark plug wires and spark plugs and was able to figure out how to gap the points correctly using the resistance measurement method (I also verified that the coils are both good and both spark plugs now spark when the flywheel spins)
*I also rebuilt the starter unit and replaced the rope
So, now I have completely rebuilt the motor but unfortunately the old thing still won't start. I know the motor has good compression because it ran when I purchased it. I know I have good fuel delivery from the tank because I sprayed gasoline in my eyes checking it

I know both plugs have good spark and the flywheel isn't hitting anything when it turns. I followed the cold start procedure and when I pull the starter one time out of ten the motor will start to run for about a second and then it goes dark.
I'm pretty sure it's a fuel delivery issue, but I don't really know what to check or do. I have concerns that the fuel pump isn't working but there's fuel in the glass filter bowl and there was oil on the spark plug tips when I pulled them out so I think there should be enough fuel to run the motor for at least a few moments.
I think I may have flipped the carb needles. Is the sharp one the high speed or slow speed?
Thanks for reading and any help.