What do you guys use to seal the firewall

[gearheads78]

Going to be putting my heater box in the 66 Cutlass back on soon. Whats everyone using for sealer. I don't care if its correct in fact I prefer it to be cleaner than how the original was done.

As a side note they did not put the sealer thick enough from the factory and you coulds see a 3" area on the fan side where sealer never touched the body. Can you say slight air leak.:eek:

[Hogshooter]

I use 3m strip caulk which is about the same stuff as factory, you can work with it and it takes many years before it gets hard.

[70LS1NOVA]

I've used windshield ribbon in the past. Seals like a champ and comes apart years later with no problem.

[BonzoHansen]

I use 3m strip caulk which is about the same stuff as factory, you can work with it and it takes many years before it gets hard.
+1 on dum-dum