STRETCH DC-9? Midwest Express buys 25 new Boeing 717s. Boeing and the Electro-Motive Division of General Motors are having some kind of contest for the longest-running series of transportation equipment (707, 720(?),727,747,737,757,767,777,7X7 and now 717 for Boeing, GP-7, GP-9, GP-18, GP-20, GP-35, GP-40, GP-38, GP-50 and the six-axle SD- series, now up to SD-90.) Who will run out of symbols first?