Magnum Heads

Hi all,
I'm trying to learn as much as I can and I'm looking at all options for upgrades for my '75 318 smog, (except a $$$ 390 stroker., can't afford.) No racing, just a cruiser with a little more HP. The 302 head is in my head now as I've got is a LD4B, 600 Eddy carb and 340 HP manifolds. I've read a lot of threads and articles about 300 to 400 HP 318's and one had to do with using magnum heads.
1.If I use 360 Magnum Heads on my 318 smog motor will it work with my LD4B manifold?
2. If not, what is the best aftermarket manifold for magnum head?

Thanks