your gonna get some material after run in, so if it was me, id drop sump and flush through, then refill, but I have never rebuilt an engine,,,,, yet

hopefully next year 1.8t going on..

but from what from ive read and seen id def take sump back off, after run in as its not a hard job and then your sure whats being going on..

could be horse poo but prob what id do, especially if you cant locate a magnetic sump plug..
Good Luck! looking forward to seeing the results!
