The master you have sounds like it should work but make sure you get the manual pedal.they can be tough to find in the junkyards but you can buy one from many mustang suppliers.Those headers arent gonna give you the most power but since you already have them go for it! Whats your engine combo anyway? You wont need any special bracket to bolt the master to the firewall. Just bolt it up.BTW the new pedal goes into the lower hole on the pedal support you will need the pedal pivot shaft and bushings if its the same as a 68.
Bob
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