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Floorboard
in glove box
== ==
To replace the headlight switch in a 66 mustang, you first have to remove the instrument cluster housing. After you have that out of the way, you will see a small button on the housing of the switch mechanism itself. Pull the switch knob all the way out, as if turning on the headlights, then push that little button and the switch stalk will pull all the way out of the switch housing. Then unscrew the switch bezel, pull the switch housing back, so that it clears the dash, unplug that big wire connector from the side of the switch, and remove the switch entirely. To install the new switch, you just do what you just did, except do it backwards.
It unscrews.
Unscrew bezel and switch should slide out through the rear (under dash)
Bad ground or bad switch
The 1966 Chevy Impala ignition switch can be removed by loosening the retaining ring at the top of the ignition switch. Remove the wiring harness. Reverse the process to install the new ignition switch.
ford mustang 1966
The top speed for the 1966 Ford Mustang is around 150 to 170
http://auto.howstuffworks.com/1965-1966-ford-mustang-specifications.htm
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