jgetti: thanks! That is just what I have. I remember seeing that article now when I was researching Spicer transmissions forgot all about it

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3B: I don't think the 348 and 409 flywheels have the same mounting

but I can have the guy that built my 496 match balance any flywheel that will bolt up it is just easier to start with a 454 flywheel. He will have to add weight to an internally balanced motors flywheel
BTW I have found twin disk clutches in 13" that work with this set up

!!
Thanks again jgetti that was just what the doctor ordered