Instead of “seperating by loose parts”, you can select the parts you want to seperate and seperate by selection. That way, the things you want ot keep in will stay and the parts you want to separate will seperate. You’ll have to do this for all the pieces you want seperate.
The other thing you could do if you did seperate by loose parts but you still wanted some of the piece together is you could select the pieces you want to put together and rejoin them with a CTRL-J.
either way would get the parts together you want together and the stuff you want apart would be apart.
