What about 2.5ish?
Not good, if correct.....I suggest that you go to Radio Shack and but 2, 10 Ohms resistors, twist them together in parallel and measure the resistance. Should be 5 Ohms. Do this to verify that your meter is working correctly and that you are doing it right. Some meters have problems reading low resistance, especially them fancy auto ranging pieces of junk that no real man would be caught using.
Also, you must either remove the brushes or unplug the regulator or the reg/rect to get an accurate reading.
The extra effort is worth it because a rewound rotor is $125 plus shipping.
If you do all these extra checks and you are still reading 2.5 Ohms, then you need a rewound rotor and you will find no better person to provide one than Gary at "Custom Rewind" in Birmingham, AL @ 800 798 7282.
You will also need a rotor puller, available at MikesXS for $10, or talk to Gary. Sometimes he has a loaner puller available. Do not even think about removing the rotor without this tool.
Gary's a great guy. Almost makes the ordeal of a fried rotor worthwhile. You'll come away from this experience a better person.