Re: flickering dash lights
Yes, better, you 've gone from 0.6 volt to 0.1 volt. Just faster control compared from the mech VR to electronic VR.
Go to the BAT terminal of alt and measure voltage - should be steady.
Make sure alt case and VR chassis are grounded and have less than 1 ohm of resistance between them.
Remove neg battery cable and wire brush all items at the battery pos junction block and at the horn relay buss bar.
Remove the junction block to ensure no rust between the block and radiator support.
Ensure the ground straps from the firewall to engine block/valve cover bolt(s) have good contact, less than 1 ohm resistance between firewall and block, not just the strap itself, but from the sheet metal to a point - alt case - on the block.
The dash, or instrument cluster, has a ground at the top of the cluster to the dash for ground. Since the dome light is flickering, I suspect the inst cluster ground is okay.
Ensure the firewall connector, the one with the large gauge red wire from the horn relay, especially the red wire, is making good contact with its receptacle.
Move battery ground from alum head/alt bracket to block, if equipped.
You also might remove fuses one at a time while viewing charging voltage.
Dome light flicker with headlights off?
You also might try another battery. I suggest this because the charging voltage is high. As a battery is used, it heats up and less charging voltage is needed. Battery charger for a couple hours? Doesn't hurt.
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