QUOTE(unggy @ Aug 24 2006, 09:44 PM) [snapback]570012[/snapback]
is it a straight replacement from my standard springs? Do i need to mod the car at all?
If by "mod" you mean "butcher" then no, not at all provided you have wheels of 16" or less. The springs are just a straight swap for the standard items and it should cost between £50 and £75 to have it done including checking/sorting the tracking.
If you're brave/talented/stupid* then you can fit them yourself. There are "how to" threads by bothe Earpl and Jaxx in the "how To" section linked from the top of the Yaris sub-forum. They're very clear and have been successfully followed by many folk. I, however went to a local independant garage who did it in a morning

Make sure you get the tracking checked - its cheaper than new tyres

Yaris SR Kid, if unggy buys there you own me a drink!

Once again, I hope that helps...
Alan
*delete as appropriate