Used this procedure tonight--it was even better than the Italian picture instructions in the box! I soldered my horn wire together with the Momo connector and then used wire shrink wrap over the connection. Altogether took about 45 mins. This is the Momo Retro.
I had the optional stock extended hub with the 4-spoke wheel. I'm very happy with the clearance with the Momo hub and probably won't install the eccentric hub extender.
I do think I need to move it a spline to the left, though. Looks perfectly straight when the car is stopped, but when I'm driving I notice its cocked a bit over to the right.
David