Larry:

I have an 88. I looked on AdvanceAutoParts site and they list a manual
mirror glass replacement.  Not sure exactly how it is on the newer
models, but on the 88, there is a mirror backing inside the "frame".
The glass just mounts to that.  So to remove, you pry the glass away
from the backing with a screwdriver (and safety glasses).  To install,
you go to an auto parts store and buy glue specific to side mirror
replacement.  Ask and the employee should be able to show you right
were it is. You squirt it on and press the replacement glass onto the
mirror backing inside the frame.  Pretty easy... should take a max of
30 mins.

James

I replaced mine in my 2000 F150 for the muth mirrors when I had one of mine
broken (Also left side) If its just the glass broken I`m not sure if Ford
sells them separately but may. They snap into little pins inside the mirror
head assembly. I may even have one for the drivers left side in storage if
the 99 and 00 are the same......

If the whole mirror assembly needs to come off you just remove the door
panel. Remove the little protective cover that hides the holes for the
mirror( located behind mirror on inside panel) remove 3 nuts and it comes
right off. If its electric you will have to remove the power cable also to
the mirror that's in the door. Its a small connector that snaps together.
Just reverse to install the new mirror assembly

To answer my own question: I went to Auto Zone. They wanted around $130 to
replace the complete driver side assembly. Not to mention removing part of
the door panel and removing 3 bolts. I told them that the housing was good,
but the mirror was broken. For around $11 they sold me the mirror only. It
is slightly smaller than the original mirror. The instructions say that if
the original mirror is only cracked, then you can put the double sided tape
on the original mirror and press the new mirror on top.

Part of my original mirror was missing, so the instructions say to remove
the remaining broken pieces. Did that. Put the double sided tape on the
base. Pressed the mirror in place. Happy camper. The product is sold by
Dorman. Web address: www.rbinc.com Product number: 51475. The replacement
mirror is two sided. Just by reversing it can be placed on the passenger
side mirror.

There is one additional instruction. "For additional strength and security
after mirror has been placed in frame, run a bead of clear silicone sealer
between the new mirror glass and housing shell. If anyone has been there and
done that, I would appreciate your advice on this.
Thanks