If you want it to split you need 4 conductor. Thatīs all.
The Holydiver and Aftermath are vaaastly different. The AM is a modern metal machine, surgically tight, dry as the desert, mid focused, agressive, hot, etc. The HD is an 80s style metal pickup with some PAF DNA. Roaring, warm, juicy, musical topend, very versatile, etc.
Really two very different ones. Can do similar things too, but they come from very different eras. Around 30 years separates them. Their spirit is related, yes, but well....
would be cool to know what your goal is here I must say.