Two tools for om616, om617 and early om603 engines designed to remove both the prechamber collar ring and the prechamber itself from the cylinder head:

One is a prechamber puller which is specific to the om616, om617 om601 om602 and early om603 engines 

The other is the prechamber ring removal tool for the same engines.  Please note that this silver ring removal tool will not work in later om601 om602 and om603 engines which were fitted with splined collar rings.  If this is the case, let me know, and I can create a custom listing for you.