After a lot of reviewing I drilled the upper firewall fittings at the firewall interface. One hole thru the forward face in the bath tub is full size (1/8") clecoing this and the other full sizs holes outside the bathtub face, I first drilled the center hole to #11 in 1/64 th steps and clecoed it then drilled the blank holes in the bath tub in one step to #30 from the front side. I used Boelube drill bit wax to help with this.
