Me again! I'm begining to feel like a stalker :?
Did mine a few weeks ago. Basically what I did was - empty the remaining petrol, filled the tank with water, supported with a jack, ground off the bolts, undid the pipes under and behind the drivers seat, slowly dropped it down with the help of my beautiful assistant (the wife), refitting is obviously in reverse. I also took the opportunity to clean the glass bowl filter, again under drivers seat.
Depending on the quality of the tank you have there may be a need for a bit of leveling off. Mine needed dropping at the front and as I had some spare rubber bushes I used those. They didn't look out of place (to me). Also a good time to find out yet another outrigger has past it's life expectancy
Pics of mine at the link
http://www.spacemud.co.uk/24.html