I have been researching if it's possible to get a 04 X5 converted into a 'crew cab' keeping the back seats but lowering the tax class. I will be using it for work. Technically, it seems that an X5 does not meet the technical dimension requirements. LWB Pajero's would for example, they remove seats 6&7.

However I spoke to a crowd in Meath who do crew cab conversions who told me they can do X5 crew cab conversions for €750 including the sign off report from a 'suitably qualified individual' (an registered engineer ) It is this sign off report which enables the vehicle to be switched from M1 to N1 tax class and to be then DOE'd.

Anyone have any experience of this ? It seems like a very grey area

There is one for sale on DD already crew cabbed.