No foolproof way to do it Ron. I run a knife blade under the feather, often times leaving a little bit of quill. Then I take a file or piece of sanding paper on a stick and file off the rest of the quill and glue.
Need to be careful with the knife as it's easy to cut into the wood and begin lifting a sliver. That pretty much ruins the shaft.
Regardless, even if you refletch over the same quill areas with the same type clamp and spiral or offset, there will be some bare spots on either side of the quill that won't look too good.
I've never tried one of those bent arm tools designed for removing feathers. Looks like they would work well on carbon or aluminum, but not so good on woodies. Maybe someone has tried one on woodies and can report on it.
Another way to go at it is to tape off the crown dip area and after you've cut away most of the quill, take some Zip Strip or similar product to the crown area. It will remove everything and you can recrown dip and fletch. Of course, it's messy and will also soften/ruin the nocks. But on old arrows, they should probably be replaced anyway.