Factory Tach conversion on 75 fury sport/roadrunner

I have a 75 Fury Sport and I wanted to add a factory tach to it. Has anyone done this kind of conversion? I have the tach, and also new ammeter/oil/fuel/temp gauges because the tach replaces two of them. I've also got the necessary fascia for the dash, and circuit board. Is there anything else that i might be missing? I'm hoping that this should plug right in to the bulkhead and fuse box. Just wanted a factory look/finish.

No help, but nice lookin' car.

Contact Instrument Specialties maybe(?)