Thanks guys for all the tips. I followed the pragmatic way of cutting short and really taking battery out only. Thanks to the cards it worked well and none of the liquid made it to any other part of the computer. Put some efforts in to properly clean the remaining glue after battery was out - but looked good and this message comes from the old mid 2012 15” Retina modell - but with the new battery in - and all is fine. I am happy - thanks to the short cut encouragement.