Tyre pressure sensors

I`ve just bought a 2007 Shelby in the UK. The pressure sensor fault sign is up and we know they are broken as they are rattling inside the tyres.
My mechanic says sensors are a nuisance anyway. Are they easy to replace ie do i have to get a full set, or is it possible just to overide the warning light and just check my own tyre pressures. Anyone got any advise ?

The car/tires should work fine without them, but the warning light in the dash can be annoying. You should be able to replace just the sensors that are faulty, and they aren't typically very expensive, at least compared to a new tire. If you're not too far from getting new tires you can probably wait until you replace the tires, but if they've still got plenty of life in them I would want to just get new sensors.

Thank you. Any ideas who would replace them, as i can`t imagine the likes of the High St tyre shops ? I`ve found them on the net in American Muscle site, but look like something that goes on the back of the valve. About £200 for 4 plus a new gismo to apperently tune them into the on board computer. However in the manual the picture looks more like something strapped around the inside of the alloy ?