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**clemdaddy** · 07-18-2015, 10:28 PM

ok… got it figured out. the original tach is a V8 tach with the signal coming from the negative side of the coil. there is a hot lead that was wired to the brake lights at the fuse block and the ground was weak that passed through the cluster. changed the hot lead to the ignition and ran a screw through the tach in the back that contacted the cluster. just messing around with it and it worked.

i will check the 63 tach that i have and if its for a 6 'the astronaut' i will let you know...

07-18-2015, 10:28 PM	#12
clemdaddy Senior Member Join Date: Oct 2009 Location: Fayetteville, Arkansas Posts: 1,932	Re: factory tach ok… got it figured out. the original tach is a V8 tach with the signal coming from the negative side of the coil. there is a hot lead that was wired to the brake lights at the fuse block and the ground was weak that passed through the cluster. changed the hot lead to the ignition and ran a screw through the tach in the back that contacted the cluster. just messing around with it and it worked. i will check the 63 tach that i have and if its for a 6 'the astronaut' i will let you know...