your using ppg epoxy and i believe that on thier tech sheet for that epoxy there is a different mix to use it as a sealer. you need to use a sealer so that the topcoat doesnt soak into the sealer. im not sure if 2k primer can be used to seal but i know epoxy can. for any other ?'s you can ask the guys at
autobody101

it's not old it's "aged to perfection"
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