Men those numbers are annoying :)
first thing.. if you have another div with the same name i would change them and make simepler path of css...
Try this:
.bulb_body {
width : 670px;
background-image : url(../img/body_bg.jpg) repeat-y;
margin-right : auto;
margin-left : auto;
}
.bulb_body_left {
width: 400px;
float: left;
}
.bulb_body_right {
width: 270px;
float: right;
}