How to use signature with GET statuses/user_timeline in C#? Trouble with OAuth


I am facing trouble in using GET statuses/user_timeline with OAuth.

I am new to twitter & programming. Most of the help I see in the documentation are for POST.

Earlier I was using :

Now based on new API, I am trying to use:
But I get “215: Bad Authentication data”.

I made an application in I also managed to generate a signature. Now i dont know how to post the signature and get the output. I using C# web forms .net 3.5. I cannot use a 3rd party library like twitterizer.