So 2990 GBP by Williams, I think (hope) the anti-roll bar is included in that price.......
I was told by Dan at Morgan that the ARB could only be fitted to the latest model due to chassis changes. Only the shocks/springs can be upgraded to the Nitrons on the earlier Plus Fours.
That makes it even less attractive. As an option from the factory incl ARB it is around 2000 GBP. So this 3000 GBP is very stiff. It means that the PlusFour from Spencer Bentley (Dales_Plus_Four), who is very positive about his upgrade, also doesn't has the ARB......! Let's ask him. I will post something on Instagram, what is pref his medium!