The statement "he will carry all these parts" can be placed at the beginning of the sentence. Alternate translation: "The priest will carry the skin ... the parts of the bull outside"
A place being ritually pure and suitable to use for serving God is spoken of as if it were physically clean. (See: [[rc://en/ta/man/translate/figs-metaphor]])
# they have cleansed for me
Here "they" refers to the priests, and "me" refers to Yahweh.