use SOAP::Lite;
use SOAP::Lite on_action => sub {sprintf '%s/%s',@_};

$proxy = 'https://proxy.com/2.3';
$uri   = 'https://uri.dataservices.training';
$method = 'methodCall';

$soap = SOAP::Lite
 ->proxy($proxy)
 ->uri($uri);

$soapenv = <<'EOF';
<?xml version="1.0" encoding="UTF-8"?>
<soap:Envelope ... (bunch of NS values)>
<soap:Header>
 (bunch of header settings here)
</soap:Header>
<soap:Body>
 (bunch of body settings here)
</soap:Body>
</soap:Envelope>
EOF

$results = $soap->call("$uri/$method",$soapenv);