What is 1984 Slant 6 timing set at?

I have a better answer.
Whatever that engine wants with the new ignition box and distributor with the carb dialed in as best as can be.
That said I've thought about trying the same carb as you got for yours on a slant before. I've worked with a few on 300 Ford's before. But never had one handy when I had a /6 around.