Well i suggested the fiesta RST intercooler because you could use all original mounts and brackets and would look factory made.I think the Transit intercooler is very similar to that of the Mondeo/Escort TD engine that would come with your engine so you might aswell use that.
Regarding the hoses, you have a long way from the front of the car way back to near the firewall.What you best do is get some stainless steel pipes made to fit at a garage which makes exhaust pipes and only use the rubber or silicone pipes to connect the steel pipe to the intercooler and the inlet manifold. Blue samcos would look nice.
If you're not using the intercooler in its original place you would be better off finding an inlet manifold from a Ford P100 pick-up (same 1.8td but without intercooler) and only change the elbow.This will save you moving the brake servo to the left. You'll understand better when you see it.You might be tempted to use the bigger turbo from the P100 hence also changing the exhaust manifold.(More boost lag but bigger kick in the arse and wheel spin )
Leaving the intercooler in its original place could save a lot of trouble.

Andy