Regarding the hammering, holding a second heavy (not garden variety nailing hammer) against the other side often helps with the impact.
The hammering is to release the tapered shaft. It doen't take much and you are only trying to achieve a quick moment of compression just at the right spot.
Or as a tech I once worked for said: "Figure you are going to whack that thing either 20 times really hard or 100 faint glancing blows ..... need more time"?
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
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