Air bag or no, there is a different horn for early and late XJS
And potentially the splines.
Searching the archives for an hour (unintended consequence of the COVID-lockdown) seems to indicate that early adopters will do it, but it will be nice to hear more opinions:
After all, Chad Bolles posted the above in 2007, there must be more 1995s with Momo or other aftermarket steering wheels in 2020.