Tru can bring it in for you... and looking up "g&p jungle series m203" in google will get you tons of pictures.
Although not trying to be a prick, if you are not ready to do basic research, then modding this to your rifle prolly isnt for you.
edit: okay, i caved, here's a review;
http://www.nlairsoft.com/reviews.php?article=gpm203