My car Peugeot 508 2013 , I bought the tool Digimaster 3 odometer correction from obd2shop.co.uk , Here is my experience use this tool,Remove dash and adjust mileage are easy jobs, the most difficult part is to disassemble BSI.
Firstly we dismantle the dashboard
Then remove BSI box
Here’s the dashboard
Be careful!!! It is very difficult to take apart BSI
Find out the 95256 chip on the left up corner. Read it and adjust odometer with digimaster III.