XPATH Select child elements whose type's element name is xs:simpleType
===

I am trying to select all child elements in the sequence whose implemented type's element name is of xs:simpleType. 

    <xs:complexType name="Truck">
	    <xs:complexContent>
			<xs:extension base="dt:Car">
			    <xs:sequence>
			    	<xs:element name="DriverName" type="Name">
			    		...
			    	</xs:element>
                    <xs:element name="Engine" type="TruckEngine">
			            ...                   
                    </xs:element>
                </xs:sequence>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>

Where the type "Name" looks like:

    <xs:simpleType name="Name">
		...
	</xs:simpleType>

and "TruckEngine" looks like:

    <xs:complexType name="TruckEngine">
        ...	
    </xs:complexType>

How would I create an XPATH to select the element DriverName? So far I have something like xs:complexType/xs:complexContent/xs:extension/xs:sequence/xs:element, but I don't know how improve my selection any further. I have had a really difficult time searching for relevant information as I am not sure what terminology to use to select something like this. I have modified my example to be something more generic.
