For more than 20 years, Katherine Legge has competed across a wide range of motorsports, racing in IndyCar, Formula E, DTM, and IMSA sports cars. Few drivers can boast a résumé like hers, but even that wealth of experience couldn’t fully prepare her for what awaited her in NASCAR. In a recent interview on The RACER Channel, former driver Paul Tracy asked Legge which series had been the hardest to break into. And NASCAR topped her list. “NASCAR, …