Fuel tank removal

I'm going to remove the petrol tank from my V8 DII and replace woth an 8 gallon tank in the rear wing in readiness for an LPG conversion. Rave suggests that the fuel system needs to be depressurised with Test Book before the fuel pump etc is taken out. Is there any other way to depressurise the system.
I intend to run the car to almost empty before I remove the tank but does anyone know whether the tank can be removed complete with fuel pump without taking the carpet and trim out of the back of the car. any advice would be greatly appreciated.

To depressurise (if required) just slacken a fuel pipe union or the pressure testing valve on the fuel rail.
The tank can be dropped with the electrics still connected but there's not much slack so difficuilt to get to, you can but is aggro. May be better to get at the the plug connections at the top of the tank via the boot floor it only takes an extra 10 or 15mins..