The 'new' injectors (2004) in my 83 SD need cleaning.

Did MB provide a port into which injector cleaner may
be directed? [In my gas cars with FI, one may spray
injector cleaner into the vacuum air line at the brake
booster to clean injectors].

Is it safe to spray injector cleaner into the air intake
at the manifold to clean out the throttle body, etc?

Thanks.