I recently purchased 2 used 318's. The starters had been removed but came with the motors. I can find no ID tags or stickers on the engines. The block of one engine has: "4006730-318-4" on the port side and "6-7-78" on the starboard side. Which starter goes on this engine? How do I determine RH or LH. I have determined the directions on the starters, one left and one right. Help!