So today I installed a different R160 that uses the male ended axles, actually used my original FXT rear axles. Seems quite a bit better but still has some of the weird vibration.
What was/is happening is, the inner cup on the axle is extending so much, that the clip that holds the cv joint inside the cup was popped out, allowing for the shaft to actually slide out of the joint, and slip, which was causing terrible noises. It only happened when there was weight on that corner, like when taking off and turning. So it appears that the axles are too short. Not really sure why, especially now that I have the exact same axles in the car, as were in there originally. It certainly isn't as bad, but it is still doing it a little. So it is fixed...sorta for now. At least my axle isn't going to blow up.