Maybe no need to reset ECU.. for Siemens-VDO, the idling will be high for a few minutes but the ECU will compensate automatically.
Removing the TB carefully won't result in torn gasket, can easily remove, clean, and put back. The TB is aluminum alloy and doesn't rust, so it's actually quite easy to clean will all sorts of solvents. Heck, I've even tried spraying diluted dishwasher and Dynamo at it. Dynamo works damn well!! You can see the black gunk just flowing right off! Then you can just hose the TB clean, wipe it, shake it to rid it of all that water and leave it under the hot sun for a while to ensure it's totally dried.
I've cleaned mine many many times by using water and dishwasher or Dynamo.. no TB damage or problems so far :wavey: