Oooo, longer shocks (from 25 squid a piece) and longer springs. Depending on what you want spring wise (I went for custom wound), expect to pay from 140 pound a set upwards - more for good 'uns.
You could use a spacer to raise the lower spring mount and these'll cost you from a tenner a piece upwards - failing that make your own.
Unless you go for lowered shock mounts you will need longer shocks as standard LR ones won't cope with extra drop required.
You may want to consider some form of camber correction for the front wheels as steering goes a bit odd (take it from me on this one) - like reduced self centering and loss of feel, especially as you wind the lock on. Mr Muddyweb went for the cranked front radius arms option - which I have to say offer the most cost effective and easy to fit solution.
HTH
Eeyore