Hello Nicholas
Welcome to the forum. I am not sure but i think a 1981 4/4 will be the Ford Crossflow engine, with a Ford gearbox , which might be familiar to you from your Lotus 7 experience. The back axle is a Salisbury 7HA which can tricky to source parts.
Parts are available for the body , chassis , suspension and brakes from many sources in the UK , not sure about France, but just ask for whatever you need and we will point you in the right direction.
