Sorry for the somewhat dumb question! Please do see if you can make sense of the latter, and put it in formal or whatever terms.

If a chariot is equal to its parts then the chariot is not its "being" equal to its parts. Else changing the parts of a chariot would be impossible – and would (?) that mean that every referent of “chariot” is composed of the same axle and wheel etc..

[P1 P2 P3 ↔ C] ← C as opposed to P1 P2 P3 ↔ C ← C
The chariot is (let's suppose) just the chariot's parts, but that fact is not something about the chariot.