You can download instructions re the Westwood version which is the same. But it seems that they are being a bit optimistic about the ease with which you can do this. Its bad enough getting it out, but a nightmare getting it back! What is not obvious is that there is a tongue right at the back of the deck that locates into a slot under the mower, and its very hard to alighn things so that it slides back in. Takes 2 people, one each side to lift and push, and ideally another to guide them! It may be that the tongue of yours is jammed in the slot: the front deck arrangement has the drawback that it is vulnerable to getting bashed and bent.
I have just bought one of these mowers secondhand, and the deck is wrecked from never having been cleaned out. I plan to drive the mower up onto a pair of car ramps to make the deck accessable instead of raising the deck. The similar Husquavana is the same. Contax have discontnued these mowers: such a pity because they seem such a good answer. BUT try phoning Countax in Oxford, they are very helpful, and there may be some trick of the trade that will sort it.
Hope this helps.
Patrick T, June 2012