Is there a way to hack Reference.svcmap to produce a specific svcutil equivalent?

Question

I have a couple of issues with the correct generation of code from a supplied set of WSDLs and XSDs outside my control. To get the right proxy class that works with a custom FaultException, I have the following svcutil params:

svcutil /t:code /out:InvoiceService_v1.cs /n:*,Test.Invoice_v1 /UseSerializerForFaults *.wsdl *.xsd /config:InvoiceService_v1.config

If I add a Service Reference using Visual Studio then the generated proxy incorrectly interprets the custom Fault definition. The settings I need aren't available inside the Visual Studio custom tool.

However, I can see the Reference.svcmap generated by the Add Service Reference tool. Inside that are a number of client options:

<ClientOptions>
    <GenerateAsynchronousMethods>false</GenerateAsynchronousMethods>
    <EnableDataBinding>true</EnableDataBinding>
    <ExcludedTypes />
    <ImportXmlTypes>false</ImportXmlTypes>
    <GenerateInternalTypes>false</GenerateInternalTypes>
    <GenerateMessageContracts>false</GenerateMessageContracts>
    <NamespaceMappings />
    <CollectionMappings />
    <GenerateSerializableTypes>true</GenerateSerializableTypes>
    <Serializer>Auto</Serializer>
    <ReferenceAllAssemblies>true</ReferenceAllAssemblies>
    <ReferencedAssemblies />
    <ReferencedDataContractTypes />
    <ServiceContractMappings />
  </ClientOptions>

Is it possible to tweak these setting so that I can use the GUI, rather than using svcutil each time?

Svcutil doesn't automatically download and parse remote XSDs, and the third party has also split the WSDL into a separate binding and interface. There is quite a bit of manual work involved to prep each WSDL and XSD before I can even run svcutil.

The GUI makes the process easy, but I can't figure out how to force it to use alternative switches.

I have already tried to add the following ClientOption but it didn't work. No error, but no class generation either:

<UseSerializerForFaults>false</UseSerializerForFaults>

Any ideas welcomed!