Hi rise intakes don't make diddly for power on the low end, they are designed to work best from 4000 to 9000 RPM. If you want to keep the intake, you have to be prepared to sacrifice the low RPM power. To make the dinosaur distributor work, might be best to throw away the points and put a Petronix system in the distributor. If it were my boat, I would take the tunnel ram off, polish it up and leave it on the shelf then put either the low rise Offy back on, or a different low rise type intake. Don will hopefull read this, he's a boat guy and would probably have some specific manifold recomendations.