Welp, to share in the joy of DIY KIA repair....

Replaced my power antenna mast on the 01 Optima tonight. KIA's tech info has
zero on this procedure. Bought the mast only online for about $15. I did the
deed and left my radio on while going through one of those automatic car
washes, good times. So, the metal mast was snapped and flopping around but
the cord within was still intact, had to cut the cord at the hole.

What I did:

1. Removed the two liner panels in the trunk to access the antenna. Two
screws, 2 or 3 of those push in deals.

2. Loosened the mast retainer (on the outside of the body).

3. Removed the antenna assembly. This was surprisingly easy, one mount
screw/nut and the whole thing comes loose (its on the bottom). Power
connector, antenna connector and a ground wire screwed to the body.

4. With the assembly in hand, I had to bring it in and figure out what the
scoop was. You have to remove the spool cover plate, did this and yanked out
the leftover cord.
NOTE: the official KIA replacement did NOT come with a new bushing so I had
to recycle this from the old one. Its made of semi-pliable plastic and can
be pushed off with a little effort keeping in mind the whole mess is greasy.
I had to remove the antenna tube as well to get at the small chunk of cord
inside.

5. Figured out how to spool the cord, the antenna cord has a ball-end that
sits in a catch/slip ring within the main spool wheel. This was probably the
most painful of steps while holed up in the corner of the trunk. The cord is
stiff and wants to jump out and you have to wind in a revolution or two to
get it fit when the antenna assembly is remounted. Even fully extended,
there was still another 8-12" of cord so you have to spool that excess.

6. Found that if the antenna is fully extended when the car is turned off,
it will automatically retract as soon as you connect the 3 pin power
connector. This is good, I was worried about it trying to extend an already
extended antenna when the radio was turned on and stripping the plastic gear
or something else bad.

7. Also found that you can't turn that sucker by hand, its not doing
anything w/o power. So you can't manually spool that way unfortunately. Its
one hand pushing down on the slip ring to keep the cord from popping out,
the other winding the spool.

8. Tested extend/retract multiple times and checked the radio, all good.

9. Carefully fastened the spool cover, tightened the top, sprayed some
lithium grease on the extended mast and re-fastened the trunk liner panels.

10. Time for a cold one.