I was about ready to respond to your first post but then read on to see that your issue has morphed. My response will still be the same however...pilot bushing. When a pilot bushing wears it allows the input shaft of the trans to engage in an "off-center" axis. How far off center changes with each depression/release of the clutch which explains how the noise changes or even goes away. The next step is the galling of the bushing which results in a "loud raspy sound". I used to run a lot of stick shift dune buggies out in the desert, the sand really wreaks havoc on pilot bushings so I have had more than my share of troubles in this area. Good luck!

 

Thanks, CharlieLed! Very helpful