360 heads on a LA 318 vs Magnum heads on a LA 318

I have just about everything of the bones of this build including both sets of heads, a few intakes to choose from, and the LA roller engine that used to be in DT, so a good foundation. I need better pistons, block work, and camshaft. Looking to make power to 6500 rpms, but the engine will decide ultimately the best place to shift. If it's 6200, or 6900, so be it.