I couldn't get the Google tool to work on the Wayback Machine as after entering my values to test with and pressing Sign nothing happened although it does seem to work if you press Sign when no default values are changed.
I found an alternative tool here which did the job and enabled me to work out where I was going wrong with the OAuth1 and it's quite useful that it describes the process it goes through:
In my case the issue was the URL encoded parameters needed to be uppercase not lowercase.