jakepressley wrote:
Jake,
Since both the owner's manual and factory shop manual for my 1990 Mustang incorrectly said the turn signal flasher was located in the fuse box, it's no wonder you are confused. When I finally found where Ford hid it (behind the radio), I also found the drain and fill plugs for the blinker fluid. They're on the firewall, easily accessed behind the heater core box. Be very careful about spilling blinker fluid on the carpet, since it's kind of smelly.
Just for the record, I don't think switching to synthetic blinker fluid is worth the additional cost. The conventional firefly spleen extract fluid usually lasts at least 50K miles, and as noted above, it's easy to change.
Hope this helps!