brake parts cleaner. spray everything out real good, all the oil ports and shit. pull out any big pieces. run regular oil for break in with a high dollar filter. like k&n, it will cost like $10 but be well worth it. it will get all the metal filings from the newly rebuilt motor as well as any of the trash that you are speaking of. run for 500 miles and then drain and put in synthetic, should be good to go