Tachometer install question on new Hemi.

I am trying to wire an aftermarket tachometer into my 70 Barracuda with a new 6.4 hemi (392) crate motor. Does any have a wiring diagram or instructions.Do I need an adapter of some kind.

try hotwire auto.com they list part numbers. you do need an adapter, at least for my stock 6.1.

Any one figured this out yet?