This post has been done first @ my FB Account, I will add some text here, as this describes my Developements & other details.
You can shop it here : https://dr-zocchi.projectweb.de/disc-adapter/
New Marzocchi Z1 Disc Adapter 1996+ Formular (FS) -> International Standard (IS) 
Another Part I wanted to do for years as I have about 25 orange Marzocchi Z1 from the beginning having Formular Disc Mounts.
Peoples like the legendary Marzocchi Z1 and after a repaint I will sell them and I like to have Disc Adapters for them using Disc Brakes!
You probably know Marzocchi startet building the orange Z1 in 1996 with Formular (FS) Standard Disc Brakes – that was the defacto Standard in that time – and later around 1999 they switched to IS.
This adapter is similiar to the well known Magura one, it will not fit to all Brake Disc Brands & Types, but with little adustments it is a perfect base & can be make easy to fit.
Further more I have been asked about Fomular Standard (FS) to Post Mount (PM) Adapter!
This is an easy task :
- simply take this adapter, it defines FS & IS standard geometry and needed parts locations
- this is a rock solid adapter, able to handle a sit-on adapter
- add a Post Mount (PM) Adapter; as there are a lot of PM Adapters, take the one which is related to your Disc Sizes
Left is a Shimano Disc Brake using additional PM Adapter with 180mm Disc Size.
Right Side is an unknown Disc Brake using additional PM Adapter with 160mm Disc Size.
