Disco 2 2001 disco 2 4.0 to 4.6 swap

got a 4.0 disco 2 manual, 140k miles and having issues - suspecting a cracked block and coolant getting in, head gasket was fine.
theres a running 4.6 p38 thor engine for sale nearby I can pick up cheap.
from a search it seems it will drop strait in and will just need the ecu programming to a 4.6.
BUT becuase mine is a 2001 and the 4.6 american option came in 2003 will this work?
also am I missing anything else? cheers

From what I know(not much)
The Range Rover engine ecu has an “internal electrickery switch” 4.0 or 4.6. Not sure if same for disco ecu but no big deal.
Gearbox the 4.0 had the hp22 the 4.6 had the hp24 stronger box. Go gentle it will last.
Change 4.6 + hp 24 as a unit and deal with all the electrickery?

All doable

J

Sorry forgot to say the LT230 won’t go straight on the 24

J

Programming the ECU (and the cruise control unit if you have it) to a 4.6L with a Nanocom is easy peasy.
Make sure the 4.6 engine doesn't have Secondary Air Induction. That is a whole other nightmare to install/troubleshoot.