On my 88 with closed loop, the heat exchanger is down low like that, but it doesn't touch the floor. Looking at your pictures, I actually think my floor doesn't extend that far under the engine. Regardless, it might be worth a look at the brackets and whatnot to see if something's come loose. It does look like it's sitting a bit low. I can't see MC designing it in such a way that the exchanger touches the carpet.