Web workflow designer - web service configuration

I'm looking for a way to control the field formatting in the web workflow designer web service task. I have an API that expects to receive the document and related fields to be formatted using the multipart form-data standard (https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Methods/POST#multipart_form_submission).

For example, if I create an API POST call in Postman using the form-data type with key/values in the body, it automatically builds out a cURL statement like this:

curl --location 'api endpoint' \
 --form 'Field1="Test1"' \
 --form 'Field2="Test2"' \
 --form 'file=@"Test.pdf"'

This is the correct format for what my API requires.

I've found, though, the DW web service task is still using the form-data POST type, but packaging all fields up as a JSON string in a single field called "requestData". Something like this in cURL:

curl --location 'api endpoint' \
 --form 'requestData="{ "Field1": "Test1", "Field2": "Test2" }"' \
 --form 'file=@"Test.pdf"'

Is there any way to control and/or modify the web service task output so it matches the first style?

Thanks!