Nothing really clever.
Owned series 2 and 2a

Series 3, bought as a van body then fitted:-
5 bearing engine
d suffix gearbox
station wagon body
full galvanised chassis

Built a 6 wheel trailer with hiab style crane

Used to rally vintage engines and tractors
Ransomes MG Crawlers etc.

Defender 90d
Basic maintenance and fitted new galvanized chassis

Discovery one
Tow pack and front hitch

Fitted a crane to my ifor Williams trailer
now building up a donkey engine to take place of the electric motor
on the hydraulic pump.

Discovery Two TD5 Auto.
Modified the rear tow pack to allow the towing of our Sankey based expedition type trailer.

Spent a lot of time involved with scouts in the past, not so much these days but still do a bit when called upon.

Anything else you will have to ask.
Happy tinkerin.