Next, it is time to position the new propshaft tunnel. This is pretty straight-forward – make sure it is a tight fit to the floor, straight, and fits snugly up against the crossmember on both sides. It is typical and OK for the rear of the tunnel to protrude past the body about 3/8″ along the topd edge back by the IRS. That’s normal and stock – don’t worry about that. Make sure you replace the little tab inside the tunnel on the RH rear that holds the handbrake cable and keeps it from getting caught in the driveshaft.