I have a 95 240sx and I'm getting ready to get the aem ems. Whenever i was looking up the part # though it had two different ones. One for a 95 obd1 and another for a 95 obd2?! How do i tell which one my car is? Sorry if this is a dumb question but I'm new to nissan and its a little different then the Honda's I'm used too. Thanx in advance for any advice.