Stan, many apologies from me as I have been MIA from the site for a while. Your clutch issue most probably was actually not a clutch issue at all. I experienced a similar issue a couple years back. I was sitting in a drive through line and my clutch started acting up. It got grabby and would not disengage unless I turned the truck off and pumped the clutch peddle. Now you would think that was indicative of a bad master or slave cylinder wouldn't you? I did, bought a brand new sealed and bled master/slave kit from the dealer. It only created and additional hole in my wallet as it fixed nothing. The clutch behaved the same as before. I ordered parts from Lary to replace my stocker with a Southbend. It was during the reassembly process that I discovered the true culprit that caused the failure. The tube that the throw out bearing rides on was coked with a mixture of clutch dust and oil. As the rear main seal began to seep over the years an oil film attracted the dust and it basically kept the throw out bearing from traveling the proper distance to fully release the clutch when depressing the peddle only once. Had the transmission and or bell housing been equipped with an inspection port I could have diagnosed and fixed it with a $3 can of brake cleaner instead of $1000 in parts. I suspect you could have as well.

https://www.dieseltruckresource.com/...-issue-301328/