Swivel seat handbrake for Renault Master

Hello all

I wonder if there are any Renault Master owners out there who have swivel seats fitted together with the necessary handbrake adaptation? We have recently received our van back from a conversion company but I'm concerned that the wrong handbrake may have been fitted. The replacement brake lever/handle element drops down when the brake is applied and this should permit the driver's seat to turn round 180 degrees on its swivel plate. However, in our case it doesn't ... the brake is a centimetre or so too high after dropping down and so the only way to turn the driver's seat round is to disengage the handbrake and then re-apply it once the seat is in its new position. Clearly this isn't right and we'll need to ask our conversion company to change it but I would like to do a bit of research myself first and find out the part number of the brake that should be fitted in this van.

Any advice of information would be most gratefully received!

Thanks

Simon