I already removed the thick black rubber using a heat gun but there's still thin rubbers left. Is there any easy way to remove this or i will use sandpaper?

 

brake clean eats away at the rubber, but it also eats the paint and clear coat.. soooo
or get some aviation paint remover and it will strip that sheet like no tomorrow.. Let it sit for like 5 mins.. nothing.. and I mean nothing will remain after that..

 

thanks dude! am going to paint it anyway

 

no problem.. just be careful, as the stripper will burn your skin if you let it sit for too long on ya...

 

ohh! didn't know that. thanks! need to buy gloves as well.