Thanks everyone, for the help
I have tried petrol, and thinners the black stuff is tough!
My Dad is an old panel beater and he said as an apprentice they heated the tar and used a scrapper.
Did that like Blocker suggested but still have the residue.
Tried the wire wheel and it did like the 3m stripper disk just spread the goo around
Might try contact cleaner.
Thanks again for the help I will keep everyone up to date if I find something that works well