Well, just to give a final update for anyone with the same problem, I got to the end of my rope to the point I was going to have the axles re-done from Step 1 in my opening post. Well, I remembered my mechanic saying that "well, you did put in a solid mount." So, going against GPF, I put stock hydraulic lower mounts back in the car, and viola. I have drove it for 2 days and I haven't felt it.

With that being said, it SEEMED that the vibration improved with everything I replaced lol. So was it in the tires? Maybe. Was it in the mounts? Partially, for sure.

So yeah, I'm glad it's fixed. Going back to stocks feel very comfortable. Guess I'll just deal with engine movement. Thanks for any and all help!

Now for my intake setup Mod numero uno.