#17 is not a regular Cologne built car.
They didnt have a rear wing, the airdam was different, and the wheelaches look more like the earlyer RS 2300 ones.
Could it be one of the Allard converted ones?
They built some with Mustang V8's in them.
Edit.
I think they gave them some weird name like "Mustapi", or "Caprang", or something like that...