The next step was (once the old master cylinder was removed) using the supplied template, plot where the holes for the studs should be and the enlarged center. I carefully cleaned the firewall and used a white out pen. That worked fine. And it's smiling at you... The instructions then suggest using a sawzall to enlarge the center hole and shape in to an egg-like form. I found that, as it is glass... hand tools and a drill are sufficient. The four bolt holes need to be enlarged. I found that on my car, under the glass, the top bolt holes were already there in the right position. Good, good ! Enlarging the four bolts required a cobalt bit. The metal is tough !!! Be mindful of the matting on the other side of the firewall. Remove the push-rod and the brake like switch bracket. Taking these of was easy. Replacing them was a nightmare. I would suggest reinstalling the bracket BEFORE putting the booster on. The clevis pin and retaining clip were not so bad. BTW the bracket and push-rod swap places. No bid deal there. Once installed, the pedal will be lower; so you will have to readjust your brake light switch.