Most people but an inline switch to the power to their gauge cluster, if i remember correctly it goes by rpm, so hitting the switch and killing the power to that cuts the speed limiter, then when your done, you just kick the switch back on to get the gauges working again.
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94' Sentra, 65' Mustang, 89' 240 Hatch, 90' 240 Hatch, 90' CA18 Coupe, 89' Sexy Gold Hatch, 99' Sentra (SR20), 95' s14 , 93' BMW 325is, 91' SR'd 240, 95' s14, 90' KA24DE-R, 89' KA24E-T (soon to be 500hp) (only a few of the cars I have owned, ugh..)
[Thunderfury, Blessed Blade of the Windseeker]