jQuery Grid Plugin - jqGrid

Hi:  Just another question in regards to loading forms with the a grid.

I've got the following:g.editGridRow(rowid,{top:0,left:0,height:450,width:450,reloadAfterSubmit:true,recreateForm:true,closeAfterEdit:true,modal:true,     beforeSubmit:function(pdata){.....

where g is my grid.

I am trying to better understand the top and left parameters as my form never consistently loads in the same place.  The position tends to be more of a relations of where the page is scrolled and not the top/left of the grid.

What I want is to consistently load any of the data entry forms at the same location on the page, with the top and left of the form always appearing at the top corner of the grid and running along it's left edge.

As per the docs:

When I look below at jqModal/modal properties it just tells me whether or not it will use the modal.js file.  If I change the top and left, ie

var ftop =  $("#ProjectTabs").position().top + "px";
var fleft = $("#ProjectTabs").position().left + "px";

where #ProjectTabs is a jQuery UI tab interface.  I was expecting the form to load at the top and left corner of the tab but it doesn't, it still loads elsewhere in the page and still seems to depend on the scrolled position.

Has anyone found a good way of setting the position for a modal form in a consistent position ?

Nathan