need advice on nardi wheel install

[Boost Monkey]

so i bought a nardi wheel that came with the screw cover ring and a horn button. i already have a momo hub and i ordered a NRG gen 2 QR which should be here in a few days. my question is what bolts do i use to bolt the wheel to the NRG hub and be able to use the cover ring?

also, how do i hook up the horn so that it will work. on the momo steering wheel i have, theres 2 terminals, + and -, but on the nardi torino horn button, theres only 1 terminal. any help is greatly appreciated, thanks