Hey Mike,
You can "test an inconspicuous spot on the vehicle body with lacquer thinner....dab a clean white cloth with lacquer thinner and rub that spot of paint. If color comes off immediately or the spot begins to wrinkle, the paint type is ENAMEL. Should color wipe off on the cloth after vigorous rubbing LACQUER PAINT is present. If NOTHING wipes off the paint is probably a type of urethane."
THIS excerpt came from David H Jacob's HWO TO PAINT YOUR CAR.
I hope it helps.
I also owe you a call back.
Thanks,
brian