I have this tan wire that is part of the harness going to the coil... old spark advance wire ? (cap off and tuck in harness)

I have a MSD pro billet dist. I am going to connect the tach signal from the dist. to the green and purple harness from my 6AL box.

I have the aftermaket MSD blaster coil made for the F-body...

color coded MSD box wiring...

black from MSD taps to car black (coil - )
orange from MSD tap to car orange (coil +)
white not used.. ( using purple & green)
red from MSD tap to heavy pink or (ignition )

how does the OEM tach interact with this so the tach is functional ?

Thanks,

 

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