The KB 243's will be above the deck, just like the original pistons.
I have them in the '68 340 in my Duster, they're .018" proud of the deck and it was left at the stock height. If you run the closed chamber Eddy's you'll need to use a thick head gasket to get your piston clearance. I run open chamber 308 heads on mine, I had them ported and cut so the chambers were 65cc's.
