Ok I just purchased a 68 440 block came with a ton of parts

Balanced forged crank
Speed pro l2355f forged pistons .30
Connecting rods
Arp everything adjustable rockers
Oil pump
Mildon pan
Windage tray
Bearings
Mp 312/590
And mildon megaflow competition valves

My question is I looked at the pistons and they seem to be 9.37-1. He told me that the valves were for 906 heads are the head specific? I was told that the engine should have 700 hp with the right heads. I doubt that but I know he was planning on using a charger which I am not. So is the compression going to be to low? And what heads would be recommended
Thanks Joe