The hose that connects directly to the turbo is different for the TDI75 and TDI90. The TDI90's turbo output points at 45° whereas the TDI75's turbo output points directly downwards. As such, the hose design is different.
Catnip64's post above confirms this to be the case.
from memory it is different size on the turbo end than it is on the end joining to the pipe going around sump. Though when i fit mine i did manage to get it wrong way around as it didn't sit quite right in the bends, seems not too difficult to do that.