I prefer to use dry ice to freeze the asphalt off. Its a bit more expensive, but there's a lot less goo and hot asphalt smell.
Dry ice and wide chisel should be able to pop them off fairly quickly. A dry ice gun would be even better, but that's a lot more money than I have.

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1971 280 SEL
1981 Volvo 242Tic | 1980 Bertone Coupe