How do you triple your January sales over year-ago numbers? Mitch Krane at Krane-Plymouth Dodge in Lapeer, MI, has found a way. Back in December Mr. Krane took a careful look at residual values and decided to capitalize on a generous discount plan for Chrysler employees. In three months he will have moved more than 230 loaded Dodge Dakota SLT Club Cabs with moonroofs and CD changers. That's more sales than the dealership had in all of 1990. He says March Dakota sales would hit at least 240. "We saw that the residual value on Dakota Club Cabs was as high as any that's out there. We saw the numbers and we jumped at it." His sales force scoured the country, buying vehicles from dealers as far away as South Dakota, Arizona and Kentucky. January was the most profitable month in the history of the dealership: total sales were $2.6 million. "We had orders for 100 Dakotas in early March and sold all of them in three days," says Mr. Krane.