Hi, That main dealer price for the ECT is daylight robbery. I ordered mine from my local parts store in Stevenage and it was less than five quid. It's an easy swap... no need to disconnect the battery! It is in a slightly awkward place but no issues. Just be careful with the wiring... don't twist or stretch and pull. Don't drain the coolant either. When you find the sensor you will see it's held in place with an elongated circlip. Use a flat end screwdriver to release the circlip... careful you don't drop it. The sensor then pulls out. Disconnect it from the wiring and replace with the new one. The only fiddly bit is getting the circlip back on, just don't drop it. For info NEVER disconnect the battery on these cars unless you absolutely have to. The result is loads of warning lights on the dash needing a diagnostic computer to reset them. There are lots of posts on this forum where people have had problems due to flat batteries or replacing old for new.