var randnum = Math.random();
var inum = 8;// Change this number to the number of images you are using.
var rand1 = Math.round(randnum * (inum-1)) + 1;
images = new Array
images[1] = "images/front/body_image.jpg"
images[2] = "images/front/body_image2.jpg"
images[3] = "images/front/body_image3.jpg"
images[4] = "images/front/body_image4.jpg"
images[5] = "images/front/body_image5.jpg"
images[6] = "images/front/body_image6.jpg"
images[7] = "images/front/body_image7.jpg"
images[8] = "images/front/body_image8.jpg"

// Ensure you have an array item for every image you are using.
var image = images[rand1]