Originally Posted by
deephate
If I would have gotten up earlier I could have sent it to Des Moines with a couple of salesmen that went there this morning. I'm taking it to Lakeside Cyclery today and have him look at it. I have PB blaster and I will try that before I break out the drill.

Hope they drive safe!
I'm not sure what material the ends are made of, probably aluminum? The end had probably corroded and somewhat welded itself to the shifter. Here's another trick I learned from an engine builder (though I've never tried this with bike parts):
Heat, bees wax, and an ice cold punch. I'd cleanup the shifter with soapy water, dry it, then put it in an oven on a baking sheet. I'd turn the oven on to 350 and let it come to temp, then wait maybe ten minutes to allow the part to heat evenly.
I'd have the punch sitting in the freezer for a few hours so it's cold cold cold!
Quickly, pull the shifter out, and melt the bees wax onto the cable head. While the shifter is secure, take that ice cold punch, and rest it on the top of the cable head for a minute. Then, turning the shifter over, try driving the cable head out again with the punch.
A drill press is also an idea, it's just kind of labor intense and requires a steady hand. Those cable heads are tiny!