Glow plug problem

Forum: 

i have recently put a 2.8td daihatsu fourtrak engine into a land Rover. I didnt have the daihatsu wiring loom when i did the conversion and as a result i fried the glow plugs because i put 12 volts to them when their only 7. Im using a daihatsu glow plug relay but what do i need/do to get the voltage down? can anyone help?
Thanks matt