Tools

13mm Socket
13mm Ring spanner
Screw drivers
Hammer
Jacks
Axil stands or Ramps
A extra set of hands

First job EMPTY OUT THE FUEL as much as possible, go for a drive, the tank is very heavy with fuel in when your under the car. Then put the car either on Ramps or on Axil stands, it doesn't make a difference which one you use. Unclip the fuel sender wire from the off side of the fuel tank, it should be held on with small metal clips. Loosen all four 13mm bolt, the two rear one you will need to use a 13mm spanner on the nut to stop it rotating. Support the fuel tank with a jack, use a piece of wood to stop damage to the tank. Undo the front bolt then the rear bolts, it's best to have someone helping at this point because the tank will still have fuel in and will try and fall when you undo all the bolts, lower to the ground. At this point the fuel tank is still connected to the car by the fuel line and the sender wire, the sender should justl pull off, the fuel lines will be clipped on. You either try and remove the fuel lines to refit later, cut them and refit with new clips, or remover the unit from the top of the tank (which is what I did, Picture top right when it's removed). To remove the unit which is on a bayonet, use an old screwdriver an a hammer to rotate it anti-clockwise, them with care pull out. Check the condition of the fuel filter.

It's a good idea to cover the tank your putting on the car with underseal, water collects on the top and it rusts quickly. (Picture top left without underseal, bottom left with underseal)

To refit, reattach fuel pipes, sender wire, make sure the fuel filler pipe is in the tank. To get the fuel filler pipe back in you will need to push quite hard. Support the fuel tank on a jack and bolt the tank onto the car, starting with the front bolts. You may have problems lining the holes back up, move the tank until you have the front holes lined up, put bolts in them then the back ones should line up. If you still can not get the holes to line up properly check that the filler pipe is in correctly. Make sure that the fuel tank isn't crushing any pipes, the tighten all the bolts. You can not check if you have connected the sender wire properly until it has petrol in it. 

Refuel

Please note: The information on this site is a guide only, no liability can be accepted for any loss, damage or injury caused by errors / omissions on this site. I won't be held responsible if you mess up yourself or your car. In doubt always consult a qualified motor technician.