I have a 79 Elcamino 305 4 bbl, want to replace the oil pan but every pan I order is different from the one on the car. The one on the car has the dip stick entering in to the driver side of the pan not the block. But all the pans I have ordered are expecting the dip stick to come in through the block. Could I have something different then a 79 305 in my car.