So ... I risked it. A little over two weeks ago I dared to do the conversion and loosened the cylinder head nuts individually. The engine was without water! Then tightened again with torque, and the head is still tight! The aim of the campaign was to create a mounting option for my heating water pipes. The conversion is now complete and works great! After 2-3 minutes, the heater brings warm air!
Here are two pictures ...
A first way to tidy up the engine compartment again.
Greetings
Andy