#1 Get a Schroth 4 point harness, great quality.
#2 Use the exisiting mounting bolts, you'll have to pull up the rear seat to get to the back ones. I was able to get to the inboard front bolt WITHOUT taking the seat out. I cut off about 1/4 inch of the plastic cover on the back side to get to the bolt, but it is unnoticable.
Best mod I have made.
Have fun!