I'm purchasing a used set of tubular wheels. They have a set of Conti Sprinters glued on. The tires have been on for a couple of years. The seller recommends regluing. These wheels are for track use on 42degree banking? Should I reglue?

If I reglue, should I take off all the old glue from the rim? from the tire? How would I do that for the tire? Any other differences between a reglue and a new installation?