Auto discovery box into a 200tdi defender?

Hi, completely new here. Just wondering if someone with more knowledge than me would know that if I source a cheap discovery with an automatic box, can I fit that to my project 200tdi defender 90 by either replacing just the box or both engine and gearbox in a straight swap style?
Thanks

Welcome to LZ.
Take a look at Ashcroft Transmissions website for an idea of what you need, or search on here.

Have seen the whole Disco set up in a Ninety so can be done. It is not a nut and bolt job, things like engine mounts and perhaps gearbox mounts have to altered as well as many nitty bitty parts.

The bellhousing from a Disco/RRC is quite long compared to 90/110, so you could run into issues having to shorten your rear prop, and find a longer one for the front..

If you're proceeding with this conversion I would also recommend modifying the 4HP22 autobox to lock up the torque converter clutch at 45MPH like the earlier Range Rover Classics compared to 55MPH like the later ones. From memory it involves changing a spring in the valve block. It makes a huge improvement in my opinion, especially as you will be driving a lighter vehicle.

Thanks for info so far, will look further into it.