Technically, these aren't actual adjectives but rather compound nouns. A compound noun is where you stick two (or more) nouns together to form a new noun. related to both but often having a subtly different meaning. The classic example is "tooth paste", a "paste" (of various substances) to clean "teeth".
The order of the words in the compound is important. The first term modifies, the second, the pair of these modify the third, and so on. So you are right that "Mercedes dream move" sounds better than "dream Mercedes move", because it's a move that is a "dream" for Mercedes.
However, "sheet metal cutting" is not the same as "metal sheet cutting". "Sheet metal" is a specific, known shape of manufactured metal, and so it sounds more appropriate to say that a business cuts sheet metal, rather than the generic and non-specific metal sheets.
I don't think there is any rule or overarching guide for this. It's just additional vocabulary that you pick up, one by one, and also common practice you learn by imitation.
Side note: A business or industry that cuts sheet metal can be described as a "Sheet Metal Cutting" business. However a machine (or a person) that cuts sheet metal is a "Sheet Metal Cutter".