renault traffic speedo conversion?

i have fitted a 6 speed gearbox into my 5 speed renault traffic 2002 model. i have fitted the gearbox and it works fine, the only problem is that on the 5 speed gearbox it has a gear driven speedo drive which locates in the top of the gearbox. On the 6 speed gearbox it is blanked off. i have been told on the later 6 speed models they dont need the manual drive as the speedo works off the abs system. Any advice on what i can do? call me on 07834217873