At Cassius ripperdock ? In hand cyberwares ?
To replace the very first one (
Ballistic Coprocessor) that you get for free at Viktor clinic at the beginning ?
If you are in Act 2 (johnny in your head and Night City fully openned), if Wakako send you the message when you visit her on Jig Jig Street and that the quest marker point out the ripperdoc, it should appear