I believe the MustangSteve CK167-P kit should be what you need. It comes with pedal to add into your existing pedal hanger, and can be used with power brakes. I'm not sure if your brake booster is wider in dimension than the ones he designed the kit around, but email him and ask. Also, add the clutch pedal bearing kit while you're in there!
 

The CK-167-P kit is the one to get when converting from automatic.  It has the clutch pedal with the quadrant welded on, the billet adjustable firewall brace and the cable, plus the pivot bushings for the clutch pedal.  While you have the pedal support out, I would encourage you to add the $40 sealed ballbearing kit to your pedal support AND also install the adjustable clutch pedal stop that comes with the CK-167-P kit.  You will simply trim your brake pedal's foot contact plate so it is a mirror image of the new clutch pedal.  Then you can install original rubber foot pads on both pedals.

With a cable clutch, the pedal system does not require 1" of free travel before engaging the throwout bearing since the throwout bearing stays in contact with the pressure plate all the time.  It spins all the time by design.  That said, it makes sense to lower the pedal about 1" so you don't have as high a pedal (knee-chin syndrome relief) and the clutch pedal requires less travel overall to actuate the clutch.  This makes for much faster clutch actuation than the old z-bar systems.  The adjustable pedal stop allows you to accomplish this.

As for booster clearance...  If you have a Midland or Bendix factory type booster, the cable will clear it just fine.  Unless you have a booster that is REAL LARGE it will not be a problem.

Complete instruction manual is included with the parts.  Also have the T5 conversion crossmembers.