Another 1974 E9 with 69-73 doorpanels. Seems to be inevitable with some interior colours, better still to use the wrong red ones than none at all. Funny you discuss whether there is too much red inside the car or not. BMW must have posed themselves the same question. In the end they did not offer red carpets, red leather usually went with black ones. By the way: the E3 came with a single part carpet from Sep. 1973 onwards. Was it the same with the coupé? This car here has the multi part set. Is that correct for a late version E9?
Next thing I am not sure about: the toolbox is the early one that ran pretty long but was replaced in mid-1974 by a much cheaper one. As a late 1974 car, shouldn't it have that later version without the black insert? Again, that's how it is on the E3.
One can be pretty sure the body is completely rebuilt. In the comments on BaT the last French licence is stated as "3300 RL 59". On French plates, the last number tells you where the car is from. Napoleon assigned the numbers in alphabetical order to the départements: 59 is "Nord", the top corner of the French hexagon, with a long coastline to the Channel. Almost British weather, quite unpleasant for quickly corroding mid-70s European cars. Probably every inch of the car had to be addressed. Even the floor panels seem to be new; the originals had the drainage holes with the bayonet lock plates but not the ones here.
Sometimes people in Germany talk about Scud. Spor. Col.; they seem to have an interesting reputation. Anyway, Ivo Christov is a well-respected gentleman, he probably knows with whom he is working.