just got a new motorguide 67lb motor.(24 volt) the previous motor was an omc 12/24 volt.. my question is this.. it came with a 4 prong plug and the one on the boat is a 3 prong.. my batteries are run in parallel i believe..(no jumper on the batteries) the new motor is 2 wire the old is 3.. i switched to the 3 prong plug and did this.. hooked up the ground and tried the positive in both of the 2 remaining slots.. got a higher more powerful speed out of the one than the other.. would this be correct to hook it up this way??