OK, I am going to answer my own question here for future reference RV10 builders.
So I made contact with Hartsell and asked them about my prop & hub STD VANS RV10 [C2YR-1BFP/F8068D. 80? diameter, ?blended airfoil ?] and spacing, I send them the Vans Drawing and they made these comments on it.
It is NOW VERY CLEAR.
If you are using the Actual Spinner Backplate as a prop simulator then:
Your Flywheel spacers will be the distance of 2.247" MINUS the thickness of the spinner backplate material. Remember this depends if you have the doubler ring installed or not.
If you are using a flat plate then your flywheel spacers is 2.247 MINUS the skirt length of the Spinner Back Plate.
I am not home to give you those thicknesses of those items though, but at least you can calculate it perfectly.
I hope that clears it up.
Regards
Rudi