Is it possible to make JSON requests using Fiddler’s Request Builder?

I think it should be more like this:

POST /ws/MyWebService.asmx/TestEvent HTTP/1.1
Host: x.x.x.x
Content-Type: application/json; charset=utf-8
Content-Length: 15

{"strData":"1"}

And it is in the connection that you specify which server to connect to.