modify a element value

<?xml version="1.0" ?>
<FDXRateRequest >
   <RequestHeader>
      <CustomerTransactionIdentifier>ewrerewr</CustomerTransactionIdentifier>
      <AccountNumber>4532434324</AccountNumber>
      <MeterNumber>34343434</MeterNumber>
      <CarrierCode>dfdfdsfd</CarrierCode>
   </RequestHeader>
   <ShipDate>2004-03-24</ShipDate>
   <DropoffType>REGULARPICKUP</DropoffType>
   <Service>STANDARDOVERNIGHT</Service>
   <Packaging>FEDEXBOX</Packaging>
   <WeightUnits>LBS</WeightUnits>
   <Weight>5.10</Weight>
   <OriginAddress>
       <Line1>ererewrewreDr</Line1>
       <Line2>Ste 567</Line2>
       <City>Indianapolis</City>
       <StateOrProvinceCode>IN</StateOrProvinceCode>
       <PostalCode>462292014</PostalCode>
       <CountryCode>US</CountryCode>
   </OriginAddress>
   <DestinationAddress>
       <Line1>Address1</Line1>
       <Line2>Address2</Line2>
       <City>SomeCity</City>
       <StateOrProvinceCode>SS</StateOrProvinceCode>
       <PostalCode>55555</PostalCode>
       <CountryCode>US</CountryCode>
   </DestinationAddress>
   <Payment>
      <PayorType>CREDITCARD</PayorType>
      <Payor>
        <AccountNumber>534657676</AccountNumber>
        <CountryCode>US</CountryCode>
      </Payor>
      <CreditCard>
        <Number>54353D5435435</Number>
        <Type>VISA</Type>
        <ExpirationDate>0705</ExpirationDate>
      </CreditCard>
   </Payment>
   <Dimensions>
     <Length>4</Length>
     <Width>4</Width>
     <Height>5</Height>
     <Units>IN</Units>
   </Dimensions>
   <DeclaredValue>
     <Value>50.00</Value>
     <CurrencyCode>USA</CurrencyCode>
   </DeclaredValue>
   <SpecialServices>
   </SpecialServices>
   <HomeDelivery>
   </HomeDelivery>
   <PackageCount>1</PackageCount>
   <VariableHandlingCharges>
   </VariableHandlingCharges>
   <International>
   </International>
</FDXRateRequest >


I wanted to change the "address1" value to something else.

is this correct way of doing this. i am new to DOM


            // load xml doc
            xmldoc = new ActiveXObject("Microsoft.XMLDOM")
         xmldoc.async=false
            xmldoc.load("FedexShipRequest.xml")

           alert(xmldoc)

            rootNode = xmldoc.documentElement

           <!-- Set Destination Shipping Address -->
            address = rootNode.getElementsByTagName("DestinationAddress")
           address1 = address(0).firstChild
           alert(address1.firstChild.nodeValue)

           <!-- Address 1 Required -->  
           address1.firstChild.nodeValue = street1
           alert(address1.firstChild.nodeValue)
           alert(address(0).firstChild.nodeValue)


           <!-- Address 2 Optional -->
           address2 = address(0).firstChild.nextSibling
           alert(address2.firstChild.nodeValue)
           address2.firstChild.nodeValue = street2
           alert(address2.firstChild.nodeValue)
           
           alert("Line2" + address(0).firstChild.nodeValue)

Thank you