Berlingo mk2 2.0 hdi gear box ratios

[berlinglow]

Hi

I was wondering if anybody might know weather the Berlingo 2.0 HDI gearbox ratios are the same as or different from the 306 box's?

I am wanting to know as in the near future hopefully before the summer my van will be tuned up to stage 2 full torque spec and if I can simply swap the box for another for longer ratios I will

Would be grateful of any help