You remarked about bnewell breaking them loose in third. He is running a 522 cubic inch motor. He breaks them loose when ever he feels like it! Don't ya Brian
Which leads to tires. All the tires available in 15", full tread, SUCK. Basically mud and snow tires with hard tread. Tires do what? Adhere to the pavement..... accelerate, brake, turn. The 15" tires in common Cobra sizes do not do these well. There are options but they have their own compromises. If you want modern performance tires, you will need to go to the 17" rims.
The tires tie into the brake figures and the abillty to easily smoke them at will. Plus, as long as you can lock all four wheels, how fast a car will stop is directly related to the vertical weight applied to the tire and the tires coeficient of friction. Re-read the tires 'SUCK' and understand these are very light cars. Add the two and you get long braking distances. (don't forget most of our braking skills!)
One drilling the fiberglass. Spin the bit back wards so that it does not flake up the gel coat. Locate the center with a hand awl before you drill and make sure the bit it perpendicular to the surface, and DO tape the area.
TAKE A DRIVING SCHOOL IN YOUR CAR. At the very least, make friends at the local SCCA chapter and Solo it.
Have fun and be safe!
Rick