13:1 Compression Pistons in 340 Small Block

Well if I were the OP I would look around for a good engine shop that knows Mopars and performance work and take what you have to them. Have the parts cleaned and inspected so you know what you have to work with. All these internet plans go out the window if you have a cracked head or worn ring lands and have to buy new parts.

After you know you have good, usable parts you can lay out a plan that will work like you expected.