i cant remember the exact post title but refilling x brand kegs has been covered on this forum.do a search and im sure you will come up with the relevant post.
the x brand from memory was tooheys.
Nice score, you might be able to land a number of goodies off him as the breweries rarely take back the gear after fitouts etc. Search for Tooheys kegs to find out how to get them apart, there are a number of topics on it. I'll see if I can find a few though.
I found this post that solved my problem for getting the spear back, works like a dream and I can remove the whole lot easily anytime I want.
"I worked out the kegs.
They are the ones with the flat metal center and rubber ring in the center.
You push down on the rubber ring against the spring preasure, lift the metal center at the same time and twist it to disengage the spear.
Then you just unscrew the top and the lot comes out.
the center spear has a 3 pin rotating locking system and one of the pins is extended to make it dificult to remove the spear.
just file it down so it still locks in but can be easily removed and installed each time by simply screwing the main top of the spear assembly."
thanks to Grumpy's forums for the info.