Hi Guys great news visa 175 granted today

I am obviously happy, however am confused, do i have to take our passports to london to get them stamped or is my grant letter sufficent to travel to oz, the following paragraph seems to contradict itself, can anyone help me cheers.

"Evidence of your visa
It is recommended that all visa holders obtain evidence of their visa in their current passport.
They can have evidence of their visa placed into their passport at any of the department’s offshore
offices with visa evidencing facilities. Details of addresses and opening times for these overseas
offices can be found at - Contact Us
Please note that a copy of this letter is sufficient for visa evidencing purposes.
IMPORTANT - Visa holders should allow at least five working days after presenting their
passport to a departmental office for the evidencing process to be completed."

Does this mean i have to take my passport to London or is taking this letter with me on my validation trip adequate, im confused and excited lol?