Not sure about the specifics of the 99. The best place I have found to get installation info is Crutchfield.com http://www.crutchfieldadvisor.com/S-Pw5yakY0qSu/reviews/installationguide/
Dear 2007 Chicago-- Circuit City has a good generic tutorial which may help you with removal of the radio from your 1999 Mazda MX5. Go to http://www.circuitcity.com/rpsm/cat/-13088/rpem/ccd/lookLearnIndex.do. You might also go to www.crutchfield.com. They have a toll-free phone number and the experts who answer the phone will be happy to answer your questions. Good luck from Bovan,
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