[Excavator]

Hello brookfloyd,
Try it like this -

#SideCategoryList li a, #SideCategoryList .sf-menu li a {
    /*border-left: 1px solid #FFFFFF;*/
    color: #FFFFFF;
    display: block;
    font: 16px Arial,Verdana,Helvetica,Sans-serif;
    padding: 8px 0 9px 30px;
    text-decoration: none;
}
#SideCategoryList li {border-left: 1px solid #fff;}
#SideCategoryList li:first-child {border-left: none;}

...
It kind of looks like you were putting two borders on your li's with this

#SideCategoryList li, #SideCategoryList .sf-menu li {
}

If that's the case, the CSS you had in place for removing the border on the :first-child removed only one border and did not remove the border off #SideCategoryList .sf-menu li



...
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