340 with 302 cast head for pickup

well I have done a ton of research now and found that the heads and his factory 10.5 to one 340 pistons wont work because it will make the compression ratio like 13.5 to one with a 54 tho head gasket way to high for pump so looks like the the x heads are going back on it along with the big mopar performance soild lift cam 528 lift 298 duration and his converter. the truck has 3.55 rear gear and a 31x10.50 tire. too much tire for the gear.