5-lugs the cheap way

That's how I did mine. It's been a couple of years so my memory is a little fuzzy. I think if you look at the bearing specs, the I.D. differs between the Mustang and Ranger, but the O.D of the bearing is almost exact. IIRC, I used bearings for a 4-cyl mustang in the Ranger rotors but left the races that came with the rotor. I didn't use the Mustang races. It's possible to use them, but it would take a press or freezing the race overnight to get it to go in. The Mustang race's O.D. is a shade bigger. I've had no problems with mine since the installation. Don't forget, you'll need to get bigger dust caps to fit the Ranger rotors. The Mustang dust caps don't fit.

The Ranger rotor is also slightly larger in diameter than the Mustang rotor. I had to clearance the calipers a tiny bit because they would rub when the brakes were applied.

It wasn't enough of a rub to warrant moving the caliper. I just took a carbide bit in my die grinder and took a little material off the caliper where I had shiny spots from the rotor rubbing the calipers. I did the swap in the shop at work and drove the car home that same day. On the way home I heard it rub when I hit the brakes and checked it out when I got in the driveway. Once I tore into it and saw what was rubbing, I took the die grinder and made a little room. I didn't get carried away, I took just enough off to keep them from making contact.

Here's a couple of pictures of the final product. They were a month or so after the job was done. They both show how much larger the Ranger rotor is in comparison to the Mustang rotor. See the rust ring on the braking surface around the outer circumference? There's your difference.

It may not rub when you bolt it all together and spin it. Mine didn't make a noise at all until it I got on the brakes going home.