OP here. So yes talking about putting new foam surrounds on the subs. You can run a low frequency signal to center the cone or like the video feel for the sweet spot. My question was how to safely send the low frequency signal to the speaker since it is 2 ohm. 8 ohm amp to a 2 ohm speaker is a mismatch. Shouldn't run higher ohm amp into a lower ohm soeaker. Probably could safely run off an 8 ohm amp low volume. I didnt want to pull the stock wiring to be able to do this in the car.

Anyway I ended up doing it like everyone else just like the video. Found sweet spot and did the trick.