The Miata had some bad water condensation buildup on all the windows a few days after a big rainstorm where the MX5 was parked outside. I brought the Miata into the garage and started looking around.
The hardtop was not leaking, and neither were the windows. I go to the trunk/boot, and noticed the floor was damp and a box in the back was damp also. The seals around the trunk were moist, but only because the moisture was trying to escape.
Finally after looking at the trunk near the tail lights, I noticed there was a puddle. Problem solved: The taillight seal between the body of the Miata and the lights was badly corroded. Hopefully I can get some new taillights out of this fix!
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