Hi,
New here, Nice site. I'm working on a 1977 LT. What colot is the tach wire in engine compartment & Can I run the factory tach off of MSD 6 al box?
Thanks

 

My schematic shows brown for the tach lead. Your factory tach should work just fine with the MSD box. I just pulled up the schematics for another guy here last week so I still have them on my desktop. If you would like I can email them to you, just PM me an address.

 

Thanks

 

JRs72RS is right without a doubt. this is something I don't even have to look up to be sure of.