If I remember correctly, you should be able to use a Lennox Hole saw if you cut a core out of a sponge that fills the inside of the hole saw. soak it with Stainless Steel cutting fluid.
Have you considered a Blue Sea #ML-RBS Remote Battery Switch, 500amp disconnect? I installed one Saturday for my bow thruster and windless. It works great with a console mounted switch or you can manually operate it from the engine room. my solution to not having to enter the engine room every...
Fuel Consumption
I ran across this thread and I do have a couple of 1985 471T, N90 injectors (rated at 325bhp) engines J & T converted. These engines run great, no smoking and very little oil consumption.
I was hoping someone would have some information on fuel consumption as my manual offers...