Old thread, but found this in a search for "9980664 Sealer". Per the AIM, (UPC 0, D5, page 21), the 9980664 sealer is applied for many of the firewall openings.
It appears the recommended "the Lord Fusor 800EZ" is different than the sealer the JohnZ refers to that was applied by Chevrolet for the firewall areas.
So the questions:
1. What is a good OE equivalent sealer for "9980664"?
2. I assume it was applied by a sealant gun vs brushed on as brushing it on for a grommet opening doesn't really make sense, correct or?
Thanks!
Hans