You can read more about the setup here, starts at post #22:
http://www.candlepowerforums.com/vb/showthread.php?180600-Anyone-seen-flexible-quot-Helping-Hands-quot-holder-that-actually-works-Answer-Yes-!!!
Wow... I forgot that it was like almost 7 years ago. I bought the same parts but I didn't drill the 2nd hole for the magnifying glass, only 1 extra hole to mount the 3rd third hand. I keep the magnifying glass separate since I don't use it that much and it has its own weighted base. The complete setup is 3 things:
1) GRS double soldering station with 2 third hands
2) GRS third hand unmounted
3) Donegan Optical 4" Flex-A-Mag
That thread has links to a couple places in the US that still sell them plus a Canadian shop I found that also sells them. This setup is NOT cheap by any means but you do get what you pay for. The base soldering station with 2 arms is $125, unmounted arm is $40, and the glass is about $30-40. If you read to the end of that thread, the last guy combined this setup with a Panavise and a pin vice that looks awesome. Another cool thing is that when you're not using it, all the arms can be folded flat onto the base so it takes up very little space in storage. I can take a picture of the folded up configuration and post that up later if you're interested.