Lower it?
Why?
A Berlingo isn't exactly a low vehicle to begin with, and making speedbump-scrapers is so... COMMON...
Jack it up! Rise above the plebeian low-riders!
Lift the roof while you're at it!
And put in a Ragtop.
Back when I got my first car (a 75 GS Pallas, a rust bucket de-luxe in 1990) the local 'Harrys' used to lower the front and jack up the rear of their cars...
(
http://en.wikipedia.org/wiki/Harry_(derogatory_term) )
I sometimes parked my GS near one of those sorry sods, and when I switched off the ignition, I pulled the height-lever to the top position. As the weight of the front pushed the oil out of the front struts, the closed valves forced the oild to the back, pushing it up to top position for an even more extreme stance...
I don't know the rules about these kind of mods in the UK, but here in Norway...
If it isn't approved by the importer or manufacturer, it just isn't legal.
(That goes for any mods to suspension or brakes. Getting forgiveness is much harder than getting permission. I know the 'DMV' guys who do the inspections.)