By test panel, I assume you are using the pumps to issue out a 2 to one ratio?

Use the pumps just to dispense the epoxy into cups for measurement or get new ones. The epoxy last forever and any cloudiness or crystallization will dissolve with heat. The pumps are not worth cleaning since it's such a mess. Take them apart with gloves and save the epoxy and replace them or just use them to put epoxy into cups for measuring.