This is a description of a petrol tank suitable for a 3.5/3.9 V8 Range Rover. The scale is not accurate but the measurements need to be precise as it fits in the rear tub behind the bulk head with a filler into the left hand side upper body. The diagrams below show the size of tank. 
Looking down on the top of the tank there needs to be 5 holes cut from left to right: - Anywhere top left Denoted by an X on the diagram. A ½ inch OD, right-angled pipe pointing in the direction of the arrow.
Upper Left Side Filler pipe.- 45mm in diameter
In the centre (vertically on diagram) - Fuel Pump Mounting The centre needs to be 45mm with the outer at least 81mm.
Far enough away to take a series pump details see series sender unit for A mm and B mm.
Anywhere top right Denoted by a Y on the diagram. A 8mm OD, right-angled pipe pointing in the direction of the arrow.
 Below is the side view of the tank. This shows how the 45mm OD filler pipe should raise up to take a 45mm pipe with a hose clip. 
The final tank can be found here | 
