Hi Geoff,
An oldie but a goodie. I threw my MP2 notes away some years ago so I don't have the codes any more. There is a site on the net that has the manual for programming the MP2. It was made by Towa so the model number is different in the UK but it is the same machine. Copy and paste this link into your browser:
https://the-checkout-tech.com/manuals/cashregisters/Towa_ET-7626_and_MR1_programming_manual.html
Registerman, November 2014