78 280Z firewall grommets

The resurrection project continues to creep forward. I have just begun cleaning up the firewall and installing a couple of small patch pieces for minor rust through areas. I have all new grommets but noticed what appears to be some type of soft sealant around the firewall holes. Was there originally some type of adhesive/sealant around the grommets, cylinder mount areas? If so ,would the 3M product # 3602-black super weatherstrip adhesive-be good choice. I have used that messy stuff with good success on other areas with weatherstripping, etc. Or, should we just install the grommets as is and call it good? Thanks again for any input, John-Lugoff, SC.