Thanks to paqogomez answer about \0
's being interpreted as the end of the string, I just added the following: -
request = request.Replace("\0", "");
I now get this in the output window which is perfect for my purposes, thanks.
----------Request Headers-----------
__ConnectionId: 16
__IPAddress: 127.0.0.1
__RequestUri: /VisaOM.Server.ClientServices.Services
Content-Type: application/octet-stream
__CustomErrorsEnabled: False
----------Request Message-----------
get_SecurityServiceszVisaOM.Client.Services.IServices, VisaOM.Client.Services.Interfaces, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
------End of Request Message--------