I know im posting in a troll thread. BUT STILL.
Cleverly jimmy the lock on his car, so that you do not disturb his alarm, or leave any sign of tom foolery. Then, disconnect his stereo console from the dash, being careful to disconnect it from the speakers, but not the power. Now, install a second stereo controller or whatever the that thing is called, underneath his seat, where it will be hidden, making sure to run the wires for the speakers through his door. Make sure that this has a CD slot. Now on to step two where you will be wiring this to control the speakers. Step 3: Rip Rebecca Black's finest tunes onto a CD and insert it into the hidden CD slot. Turn volume to max.
Step five: Profit.
His car will become a source of pain and misery and will be seemingly unfixable. Not wanting to get into his car for fear of torture, he will stay home, slowly cutting him off from his friends and social life. Soon, his friends will cease to talk to him, and the vultures of depression will set in. Week upon weeks he will lie in his bed, crying, trying to find the strength to get out of bed but will not. The world hates him. He will soon resort to drastic measures, such as drafting his own suicide note, slitting wrists, and overdosing on medicines. Eventually, the pain of this world will be too much to bear, and he will slip into hysteria, forever shrinking in to his mind. His body will be left to decay, a zombie of sorts. His parents will weep and attempt to coax him out of his stupor, but he is long gone. The damage will be so immense that by the time his life is finally taken, it will be considered a gratitude, and your revenge shall be complete.