I wanted to post the answer that someone helped us with.
You should be using new custom theming for this<aura:component implements="forceCommunity:themeLayout" access="global" description="Sample Custom Theme Layout">
<aura:attribute name="search" type="Aura.Component[]" required="false"/>
<aura:attribute name="profileMenu" type="Aura.Component[]" required="false"/>
<aura:attribute name="navBar" type="Aura.Component[]" required="false"/>
<aura:attribute name="newHeader" type="Aura.Component[]" required="false"/>
<div>
<div class="searchRegion">
{!v.search}
</div>
<div class="profileMenuRegion">
{!v.profileMenu}
</div>
<div class="navigation">
{!v.navBar}
</div>
<div class="newHeader">
{!v.newHeader}
</div>
<div class="mainContentArea">
{!v.body}
</div>
</div>
If you still want to override the profileMenu you can do using below code
<aura:component implements="forceCommunity:profileMenuInterface" access="global">
<aura:attribute name="options" type="String[]" default="Option 1, Option 2"/>
<ui:menu >
<ui:menuTriggerLink aura:id="trigger" label="Profile Menu"/>
<ui:menuList class="actionMenu" aura:id="actionMenu">
<aura:iteration items="{!v.options}" var="itemLabel">
<ui:actionMenuItem label="{!itemLabel}" click="{!c.handleClick}"/>
</aura:iteration>
</ui:menuList>
</ui:menu>
After you create a custom profile menu component, admins can select it in Community Builder in Settings | Theme to replace the template’s standard Profile
