Diesel conversion 1995 Disco 3.9 litre help!!!

[99Rover]

Hi, my name is Geoff and I am fairly new to the land rover family....I am thinking of buying a great trail ready D1 but I want to swap the stock
1995 D1 3.9 liter gas engine with the corresponding year's TDI(as used in camel trophy) I would love any feedback regarding the conversion
-is it possible?
-modifications?
-cost?

has anyone tried this?
Thanks!