Well, it seems I had the right type of puller afterall, but I could not for the life of me get the bolt undone on the balancer. As the car is auto, I tried to hold it still with an old drive belt and stop it spinning, and it worked, but with my weight (80kg)literally hanging off a 70cm breaker bar, it still would not budge, but the belt did, so i fell to the ground. anyway, I also tried the relay trick, turning the engine over without spark etc. This did not work either, as i was only using some wire and not a switch. So I gave up in the end, as light was fading fast and I had to drive the car home. Hopefully in the future i will somehow remove this bolt.

Goto a mechanic and ask them nicely to rattle gun it off, then do it back up with normal tools, then you should be able to get it undoen to do what you need.

Hmm... only thin i can think of, sounds you've already tired.... place the socket on the bolt and rest the breaker bar on the bottom of the engine bay... attempt to crank the engine over and it should come loose... eventually (took a few goes on my 5.0L to get the seal to crack).

Yeah, I tried the starter method but as I was only using a piece of wire to bridge the terminals where the relay goes (as opposed to the proper switch I presume you use) it wouldn't work that well. I'll try and get a mechanic to crack the seal for me, and i'll do the rest from there. Thanks for your help guys.