I second SDTG.
Jacking your pre-pay meter is highly dangerous. Not only might you electrocute yourself, your family, your neighbours or friends, it can also create extraordinary problems in the wider neighbourhood.
We have had years of problems with our electricity supply (daily power cuts etc) because people have been jacking the grid in our area and bypassing meters. It got very bad when a cannabis farm did it and drew down extraordinary amounts of power from the grid.
The subsequent instability of the supply (repetitive power cuts after only a few minutes of power returning after a previous power cut) damaged a lot of people's electrical equipment in the area. It was frying people's PCs, sending house alarms off at all times of the day and night, resetting alarm clocks, cutting out oven timers, damaging clothes as washing machines would stop working, but more over, it was causing a lot of accidents as people tried to move around in the dark. One house had a small fire because a candle fell over onto a rug.
I know a number of work from home people who lost a fair whack of money because they lost work or had to replace damaged electronic equipment because of the supply issues caused by other people jacking the grid. It damaged one of my PCs beyond repair and I had to fork out £400 for another one.
People are seeing this issue as a "victimless crime" but, in truth, there are very few victimless crimes. It is just that people cannot see the victims in these cases because they are not immediately apparent.