'The pronoun wants to be used' is incorrect. You can say 'The pronoun needs to be used' or 'The pronoun should be used ..' or ..etc, in so many ways. My two cents.
In English you have an fixed word order, except in interrogatives and exclamations.
It looks as this:
Subject + verb + object/complement - this is how an affirmative sentence looks like, normally.
From this your sentence 4. Max cleaned up it, is correct but since it is a verbal phrase consisting of two items you need to split them up and put the pronoun in
Uhm, I think "Max cleaned it up" is correct. The question here is where we put the object. Am I right?! If a transitive phrasal verb ends with an adverb, we have 3 possibilities!
1. If the object is a noun phrase, you can put it ever before or after the adverb. Example:"Max cleaned up the garden" or "Max cleaned the