There is a little panel/cover in the back, right and left side, that just pops off and give you access to the tail light assy. Twist out the bulb, install new, twist back in and replace the cover. Have a beer....

If you cant access it well enough that way... the whole black side piece can also be taken out pretty easily... just held in with about 6 of those little black push lock things... (it may be easy to me because I have done it several times. Your view may be different.... )