1988 Mustang overheating

I have a 1988 Ford Mustang LX with an electric fan. Ive installed a new fan, fan motor, radiator cap, and coolant sensor, but the car still overheats. I checked out some wiring that goes to the electric fan motor, but there is no power, then entire line is dead. I dont know where the end of this wire is, so I cant fix the problem. My question to you guys is, since Ive changed everything in the radiator and coolant region, is there any kind of electric wiring that may need to be done to get the power back to the motor to stop it from overheating? If you have any ideas Id appreciate it, also if you know where the location of the electrical center piece may be that would also help. Ive worked on this car for years, and this is the first problem that really stumped me.