I'm about to buy a speedometer cable from http://www.hondaautomotiveparts.com. And I'm not sure if I should just buy the cable which is #1 on the diagram, or should I also buy #4 which is the cable assembly. Its under Combination Meter and its for a 1990 honda civic si. I would rather just buy the cable and save some cash but if I need the whole assembly I'll get it if needed.