I put together this video when I replaced the antenna mast on my brother's 2003 XJ8. I actually did NOT have to remove the motor because whomever broke the antenna off, pulled all of the mast rip cord out with the end of the antenna. I had no way of knowing that so I pulled the motor.

This video will show you both ways. I hope it explains it all for everyone that needs to replace a broken antenna.

NOTE: It is a good idea to lubricate the antenna shaft monthly or every so often with WD-40 or some other lubrication so the antenna doesn't get stressed when dry.

 

I just had to replace mine. the mast was intact, but the plastic geared strip was broken, so I had to pull the motor and disassemble to get the broken piece of the geared strip out.

For those who are interested I found the mast on Rock Auto for $9.23

Here is the part number LNA4134AA