A 3 finger Borg and Beck or Long style can be disassembled, springs changed for different clamp loads, (based on friction material) and pressure plate face resurfaced. A diaphragm style is a throw away. This is my spare for my B body.
This and part of the reason is the tight tolerances. If you were to re-surface it, you would have to ship the spring, etc, and that is not a job for us "back yard" guys
On a side note, I ran my 340 swapped 440-6 Roadrunner with a ? 70's ? Corvette diaphragm and it worked great. Removed the over center spring.