I'm currently stripping my interior in my 67. Right now my focust is on tear down, and I'm finding that on all the main interior weld points (floor pan), there is a tar-like substance. This is a royal pain to remove, and I can't for the life of me imagine what purpose it serves...

Is there a justifiable reason for this crap to be there? And, WHAT TAKES IT OFF? Is it truly tar, some adhesive residue, some sticky, solidified 40 year old mystery glue? It is not seam sealer - that I discovered too, and it is completely different. This tar-like crap has collected where the seat mounting plate, and floor pan meet, as well as where the floor pan and firewall meet. What gives???

I wore out (broke) my drill trying to grind it out with a steel wire stripping wheel.

Any advise, help and / or guidance is GREATLY appreciated!

Thanks!

This stuff was used to seal the seams. It is very much like tar. Mine was hard and brittle so I was able to get most of it out by just getting under it with a screwdriver. After that, I used lots of rags and paint thinner. Finally, I used my angle grinder with a cup bursh, or one of those poly fiber discs. It takes lots of time. I suggest you buy an angle grinder. They are cheaper than buying multiple drills.