Parallel parallel would get you to .5, series parallel would get you to 2ohm,,,, for 4 subs at 1 ohm final reading you would want dvc2, parallel parallel get you to 1ohm. Stop by the shop, happy to help you out.
There are a lot of factors that will affect the way you should wire them such as charging system power wire size, etc. I would visit the store and tell Mike what you have. He is very friendly and willing to help. Good luck!
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