Tar-like undercoating on 63 Valiant...any way to remove it?

If it ain't broke don't fix it.

The tar is the factory undercoat.
It has done it's job for 50 to 60 years.

Fix areas that need fixing.


If you are hell bent on removing it...

I removed some from a fender with propane torch, watch the flame and the tar catching fire. It tends to self extinguish when you move the flame away.

What I did was heat up an area then use a scraper to scrape it off.

I would look for some high temp plastic scrapers so to not scratch the paint.