I can't answer your question but there are a lot of Land Rover enthusiasts out there who could. I think you could make contact with them by visiting more specialised forums than this one.
I suspect a Td5 conversion would benefit the vehicle and yourself if it is possible.
I think there will be many small but important differences between the two models and you should do some research to discover what they are and whether it is economic to go ahead. I think just being able to source the Td5 engine will cause many complications, much time and expense. Having a complete donor vehicle at hand is the only satisfactory way to convert two otherwise identical models. This applies just as much when the models aren't identical, even though many brackets and the exhaust system will probably have to be manufactured, wiring modified, space made for the intercooler, electronics changed over or modified and perhaps the original transmission won't be big enough to house the clutch and flywheel.
Almost any engine can be fitted to any vehicle but it is rare conversions are simple nut-and-bolt affairs and mostly some engineering is needed. Some conversions are almost entirely engineering. One important thing to remember is it can be difficult to maintain a converted vehicle due to access problems and the difficulty of obtaining spare parts. Specially engineered parts will not be available.
Answers & Comments
I can't answer your question but there are a lot of Land Rover enthusiasts out there who could. I think you could make contact with them by visiting more specialised forums than this one.
I suspect a Td5 conversion would benefit the vehicle and yourself if it is possible.
I think there will be many small but important differences between the two models and you should do some research to discover what they are and whether it is economic to go ahead. I think just being able to source the Td5 engine will cause many complications, much time and expense.
Having a complete donor vehicle at hand is the only satisfactory way to convert two otherwise identical models. This applies just as much when the models aren't identical, even though many brackets and the exhaust system will probably have to be manufactured, wiring modified, space made for the intercooler, electronics changed over or modified and perhaps the original transmission won't be big enough to house the clutch and flywheel.
Almost any engine can be fitted to any vehicle but it is rare conversions are simple nut-and-bolt affairs and mostly some engineering is needed. Some conversions are almost entirely engineering.
One important thing to remember is it can be difficult to maintain a converted vehicle due to access problems and the difficulty of obtaining spare parts. Specially engineered parts will not be available.
Good luck!