Automotive Plastics: Most efficient tool to scrape off polyurethane, polyurethane stains removal, steel wool

Question
I've been building car roofs and I filled the interior of the roofs with hard polyurethane foam, but I need to scrape off the excess foam from the surface of the beams prior to putting on the upholstery. Right now I use a saw to scrape the foam off. I wonder if there are any more efficient automatic/electric/air-powered industrial tools to scrape off this foam. Thanks in advance.

PS. Maybe some solutions that would ease the removal of the polyurethane would also help. We've tried acetone but it's too costly.

Answer
Hi John, I have successfully , dealt with some stubborn Polyurethane stains  by heating steel with the heat gun and before they dry, removed them with a medium coarse steel wool. I have also used Sttodart solvent ( Varsol ) in certain >PU< formulas with good results. What about using an electric orbital sander? Thanks.