msd 5

Hey guys one of my friends has a crx with a 1989 si distributor, and he just got a msd 5 part no. 5200 ignition. We looked on the net and found a owners manual that says the red wire is to the coil pos, the orange is to the negative, the black is the ground, and then there is the white wire that says it goes to the electronic trigger. My question is what is the electronic trigger, and what color is the wire, and is it on the coil or the box under the coil in the distributor? Any advice would be appreciated.