Metamod Show Only Right Column on Product Page and make other pgs width 100%

Hi. Please help if you know this. I am using Joomlart JA-zeolite and I created a metamod module that is set to the position "right" (the right column). All the modules that suppose to show up in the right colmun is set posistion to the metamod module. And I used the following php code to make them only show up on VM product page. All other pages such as article page should not have the right column, the main content area should be 100% of the page width.

if ($option == "com_virtuemart") {
$page = JRequest::getVar("page");
$product_id = JRequest::getVar("product_id");

/* PRODUCT DETAILS page */
if ($page == "shop.product_details") {
  /* modules that should appear for specific products */
  if ($product_id == "34") return "metamod-right";
}
}

This worked partially, the containing modules does not show in the right column of other pages except product page. However a blank right column is still there. Blank divs are all still there. <div id="ja-right"> and the main content area width is still 73%. <div "ja-mainbody" style="width:=73%"> and I still see the empty metamod module, <div id="Mod142" class="ja-module ja-box-br module">.

Is it possible to make the div "ja-mainbody" width:=100%? This seems to be needing php hack.

I am using Joomla 1.5.22, metamod 2.6

Thank you.