DETROIT — The corporate Red Letter Dodge blog has thrown down the Halloween gauntlet to fans of the Dodge Challenger and . In advance of the October 31 holiday, it is offering stencils and instructions for carving a pumpkin with Hemis and horsepower in mind.'Make your porch the coolest in town,' says the blog, which offers a link for downloading copies of stencils at Flickr. Pumpkin carvers who post their handiwork at the blog are eligible to win a 'prize pack' which includes a limited-edition Dodge Challenger shirt. Can a Chevrolet Volt pumpkin-carving contest with a Frankenstein theme be far behind?Inside Line says: That punkin got a Hemi? — Paul Lienert, Correspondent