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Will a 1992 mazda miata hardtop fit a 2000 mazda miata?
There is no fan belt on a Mazda Miata.
NO
In the trunk, passenger side
Should, I believe you will have to switch the seat frames though
The 2000 Mazda Miata O2 sensor bank 1 is located on the firewall in the engine compartment. The sensor can be found on the passenger side of the firewall.
http://www.clearwateraudio.com/miata.htm
3.8 to 4 quarts of engine oil.
Yes. Bear in mind that 1999-2000 leather seats are considered the worst seats amongst Miata owners due to poor back support.
You can purchase them new from http://www.finishlineperformance.com They are actually a Mazda Dealership that has very good prices on OEM Miata items. New, the price is currently $25 USD. Click on the Mx-5 Mazda Miata link, then to the Maintenance section. You'll see the manuals on sale.
In a 2000 Mazda Miata, the turn signal flasher is located under the dashboard, specifically near the steering column. You may need to remove the lower dash panel to access it. The flasher is typically a small cylindrical component that can be easily unplugged and replaced if necessary.
If memory serves me well I think it is located directly under the center console.