There are several pages on using dry ice to remove hail damage, even youTube..
I'd try this first,
You can find dry ice in many places these days, even your local grocery store. It's cheap too, around $2 or less for a pound (you can buy it in bulk online for even cheaper). All you do is touch the dry ice to the dent for a few seconds and repeat the process until the dent is gone. Wear dry ice gloves though.
Remove Car Dents Quickly and Cheaply | Wise Bread
Cars and TransportationApr 20, 2007 – Remove a dent with a lighter, aluminum foil and an air duster ..... I used dry ice on my hail damage when it was 108° F outside, with no luck. ...
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Jul 18, 2011 – The Web's leading source of Information about Dry Ice. ... DENTS & HAIL DAMAGE Dry Ice will condense ... REMOVE FLOOR TILE Dry Ice will ...
Paintless Dent Repair for Hail Damage - Atlanta Dent Repair ...