My RD shifter is SOL. I have a couple friction shifters I'd like to use, but I can't figure out how to remove the cable from the shifter. Does anyone have any ideas on removal, or are these something where I need to snip the cable and put a new end on it?

Check out the Shimano Techdocs for your shifter, this will show how to install a cable, just reverse the process to remove

Shimano doesn't have this model on their techdoc site.

Edit- finally got all the little clips off and it looks like the end is crimped on after it's put through a piece of plastic so the only way to pull it is break the plastic piece or cut the end off of the cable.