Hi all. I am trying to install a Personal steering wheel from a 1975 Spider on my Duetto. I immediately ran into a bit of a problem. Both wheels are keyed and fit onto the steering column, but the original steering wheel's hub is shaped differently, in that it extends deeper onto the column and it seems to make space for the plastic steering column cover. The hub of the Personal wheel is essentially flat, so it rests against and rubs against the plastic "clam shell". That keeps it from sliding down onto the column as deeply as the original wheel to expose all/enough of the threads for the mounting nut to securely install the steering wheel. Is the series 2 spider steering column longer, or is the plastic column cover shorter? Help! Thanks in advance for any responses with advice.