I'd contact a bosch service center and confirm the stud is simply a stud and if so get a replacement, pull it out and install the new one. Should be fairly easy.

What torque did you use on the delivery valves?

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)