95 Silverado Tach, speedo, odometer dead

To All,
On my 1995 Chevy Silverado 350/4L60 the Tach, speedometer, and odometer are dead. I replaced the vehicle speed sensor, then the ignition switch, checked the fuses. STILL nothing. What am I missing or what can I look at? The gauge housing and circuits all look good.
Thanks,
Larry

I installed a new head unit into a friends 94 Silverado and at one point I bumped a wiring harness behind the radio mount and his tach went out. I took it all back out and everything looked like it was plugged in tightly, I jiggled a couple and tried it again and it worked. I would suggest playing with every wire and connection you can unless you did already.