Thanks for all of the support y'all. I stayed away from the car for a little while and went out this morning. Yes the master cylinder unbolts via the firewall, but the problem I had was the pushrod would not come out of the mc. I had to undo a clip underneath the dash to get the entire assembly out. I then got the pushrod out by placing the mc in a vise and pulled it out. Then I see that the piston is formed on the pushrod. A dremel tool quickly got rid of the old piston. I ran out of time and had to go to work but I hope that the old pushrod is compatible with the dual mc I plan to install.