HELP! 88 Thunderbird.. Broken gauges, runs/shifts funny

I have an 88 Thunderbird LX, not a Turbo or Super. It has a 5.0 with around 170k on it.
Last month the temp, oil, and fuel gauges stopped working. This was fine until last Wednesday it started running/shifting funny.
I figured it was trying to get code from the cluster, so I replaced the IVR, since that's what brings the usual vehicle 12v down to 5v for those 3 gauges.
Well, the gauges still don't work, and it still runs/shifts funny...
What should my next step be?
Thanks Steve
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Anyone?

around
IVR,
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SMoo opined in

1. Find out if you're getting 12v TO that IVR. 1a.Check grd ref on inst cluster to dash frame
2. Check all grounds, including engine to firewall, and the ground adjacent to the ECM (pass kick panel)
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