Its been a while since i had any Naomi Universals but that looks like a mechanical coin mech, the UK Naomi Universals I have had in the past were all setup for multi coin mechs, with those you dont have the mechanical microswitch mounted at the bottom of the mounting bracket on the lower control panel which you will need with a mechnical mech, they wiring is also different as the multi coin mechs use a small PCB to interface to the JVS I/O board.
So depending on what your cabs setup with you will likely need the additional bracket with the microswitch mount and you will also need to modify the wiring to the JVS I/O to go directly to that microswitch instead of the multi coin PCB.
Manual here, all the coin mech stuff is at the very beginning -
https://www.hard--candy.com/wiki/uploads/NaomiUniversal/Downloads/NaomiUniversal-Manual.pdf