Hyundai Motor Group is closing in on Ford’s position as the third-largest automaker in the US, with strong hybrid sales putting its first quarterly — and potentially annual — third-place finish within reach. Hyundai Motor and Kia outsold Ford in July and August, building a lead of more than 15,000 vehicles over the two months. But sustaining that momentum could become harder as Washington relaxes fuel economy rules, giving US rivals more room to focus on their profitable gasoline-powered SUVs an