Please help ..headlight broken..thank you
 

Hi everybody im Valentin and i am from Franklin tn ...recently we got a 2013 GL450 for my wife and aside the HUGE gas consumption everything was ok until the right light went out and to find its not the bulb(xenon) and probably is the ballast...well few days later the left headlight went out light and blinker ...from water that got into the housing from rain...i had 1/2 inch of water collected in the corner and glass was all fogy .....plus the back up camera work only when is a little cooler outside which it was few times
with all this i went to nashville merc dealer hoping my full coverage extended warranty will cover all or at least something....well nothing its covered.....and the quoted me $3400 for left light assembly ,and for the camera they just did a software update and so far it worked
So please obviously i want to try to replace or fix it myself but im kinda confused because its not just the light housing...its i guess a module and ballast...i do have the adaptive cornering lights...
dealer said in order to replace the light the bumper needs to come off then it needs to be coded after ...which will cost about 200....so please any input in removing the bumper and steps to fix this...thank you thank you