I think my brother is pretty motivated since we have been making good progress. He has been coming home from work to get **** done.
I filled in all the extra holes that were drilled in the floor and raised up the tunnel just a bit to give us a bit more space around the transmission:

My brother stripped all the rust and brushed on some epoxy (we were too lazy to strip the floors):

Got some knock off dynamat:

Applied it to the areas that sounded hollow when we knocked on them:

Put a layer of closed cell foam to act as a decoupler:

Then mass loaded vinyl on top:

Still need to work it down on to the floor more. The stuff is thick and hard to shape.