Tim,
There are only a few ways to take the grip off and most all of them involve some cutting, at least down to the adhesive level. Usually, getting to that level will not get you into the blank, then use hot water to loosen up the adhesive and most of the time it will peel off. you can use acetone to remove most of the residue.
As far as the finish goes, a lot of blanks are painted like you have suggested and you can replace the color with a very good high quality spray paint then overcoat that with a clear gloss. A lot of restorationists are using sprays and using airbruch techniques to apply them. It gives you a bit more control of the quality too. Some like to dip them to get a good finish and I do dip some of the older fiberglass that I restore. That can be an expensive sedt up for only one or two rods though.
Unfortunatley, removal of an old finish chemically usually has an impact on the finish and the paint on painted blanks. If the color is a part of the coating and not painted on, you can remove the old clear coat with citrus strippper and it won't impact the epoxy coating. Pay close attention to the finish after applying it and when it starts to lift, apply just a bit more to keep it moistened with the citrus stripper and it will come right off.
Are these rods graphite or are they fiberglass?