A good auto sparks could adapt the wiring and with the use of a relay, a pair of twin tone horns could be installed..The original horn could always be re-installed at a later date.

+1 The biggest problem on modern cars likely to be where to find room to fit the horns.

Seems strange that manufacturers spent millions getting doors to shut with a thud and switches to 'feel' right, then put a nasty little peep peep horn in.

Many thanks, seems that is probably the only road to go down. It's just that it would invalidate my warranty, and insurance if they found out.

Thanks anyway.