Fender 300 auto... how to?

I've touched on this a couple of times in the past but it's getting close to being a reality so I need some sound advice please.

Due to my accident a few years ago I can now only drive an auto, with hand controls. The hand controls are easy to sort (Jeff Gosling are nearby and they did my Disco) but I'm going to have to transplant a Disco 300dti engine and auto box into a tratter since I don't want to spend £10g+ on the anniversary edition.

Which brings me to my question: What year/model of fender will accept a straight-swap of the 300 block and to what degree will I need to modify the gearbox mountings to make an auto fit?

Other niggles like the oil cooler I can fettle into place, as long as I can get the lump in place belt & braces first.

Body-wise, I'd prefer to use a 90, but am open to other possibilities. Would even considered trying a series if the block will fit. Also, Dorris & the kids want me to make a ragtop so this is worth considering.

Any advice would be most welcome.

Ta!

Any 300tdi defender will take the disco 300 tdi with auto , without any mods to engine mounts or gearbox mounting (you can use the disco auto cross member with small mod (2 cutouts to miss bolts) . The oil cooler for auto can be mounted just in front of rad , cut off end of disco trans cooler pipes just at front cross member and fit hyd hose upto cooler . The front down pipe will connect up to defender system (same parts ) Some change over FIP as disco 300tdi auto is EDIS ( fly by wire) but I have managed to use the edis and also gives you an immobiliser. You will need a TD5 speedo and a td5 speed transducer. The airflow meter sits about same place as on disco and I used silicone pipe to connect back to a DT air cleaner mounted at rear of engine The washer bottle gets moved to a new bracket mounted above where clutch pedal used to be . The auto changer mounts where centre seat was . Just done all this to a 90 rebuilt for my daughter HTSH

My current auto is an older one (not fly-by-wire) so a slight variation on the theme if I decide to use this one as a donor but great info if I go with a later engine for the job.
Thank you.

If you go for a pre 300 defender , you also need to change or mod seatbase, and centre tunnel , the pre edis would be a simpler fit esp with regards wiring . Regards a 90 if you have kids seating could become a problem eg forward facing seatbelts etc .

Hadn't thought about kids not facing forward. A 4 door would be more practical too...
Hmm, plenty to think on. Ta.