Building a 340 engine

I've been looking at these.
ICON Premium Forged Pistons IC741-080
They would also be going into a 340 that is already .040 over with a 340 crank. There are also 9.6 and 20.5 cc dish tops anddifferent bore sizes available.
CHRYSLER 5.9L/360 Mopar small block LA ICON Premium Forged Pistons
What's the highest available octane fuel you have? Based on a 9.6 inch deck height, these pistons come out .012 under deck. A little milling would get you to zero deck and then you could select from several different head gaskets to get something that resembles quench.

I have read that you should not go more than 0.030 with a 340 block
We got gas with 98 octane