Chicago referral

Replacing a tail light assembly is not at all difficult. You might give it
the old college try before paying someone else to do it.

While I can't find any Gen III specific instructions, here they are for the
Gen II. I doubt that there are any significant differences.

http://priuschat.com/forums/gen-ii-...423-2007-tail-light-removal-instructions.html

I've replaced both of my Gen II assemblies. My only caution would be
to ensure that the new assembly sits firmly against the body work. This
is the only seal to keep water out of the interior. If the joint does leak,
water collects in the spare tire well. Check after the first good hard
rain. If you forget, you'll know you have a problem when you hear
sloshing sounds from the rear.

When you check the spare tire well for moisture, it's a good time to
check the oft forgotten pressure in the spare.

 

I just did mine. It was not a ome, but was a good fit. As I recall there were 3 maybe 4 fastners to screw in. A real easy swap.