On my 75 f100 with a 390 were would I connect it to for tuning. The meter has two wires comming from it with gator connectors on the end.
I wanted to connect it to so I could use the tach to see were my rpm's are at idle.

 

Red clip to the negative side of the coil, black to ground.
Hope this helps.
Greg

'77 F-250 Camper Special 400ci driver
'76 F-250 Supercab 360ci current project
'71 Mach I 429CJ in storage
'79 F-150 for parts
huct on foniks wurkt fer me

 

Thanks, I was not for sure about the red clip.

 

If you have the Durafart for '75, the coil primary posts will say BAT and DEC. Connect the red clip to DEC.

Barry