This is why ultrasonic cleaning of all components is required during the repair process of any engine.
There's no other method that will remove the debris as well as it lodges inside the passageways of the case and becomes caught in the rough casting areas of the case.
During operation, hot oil will wash this debris into the oil where it becomes suspended and then delivered to other components, or the replacement IMS Bearing, and the whole ugly process starts all over again.
Cleanliness is the #1 factor that determines the success of any repair made to these engines.
You guys must have never heard of a filtermag before :-)
Equip that engine with an LN Spin On Filter Adaptor and equip that filter with a filter mag.
This is all outlined here and was written from our direct experience.
Bearing already failing?
I would have changed the oil after 3 minutes of run time, then again after 10 minutes of run time and again after 30 minutes and again after 30 miles. Yes, you will change oil a lot, or you will waste an engine. Don't use synthetic oil for this, use some cheap conventional crap that you don't mind throwing away. It will generally gather more debris than synthetic oil will, anyway.
What hates material laden oil more than anything is the variable valve timing components and lifters. The ferromagnetic dust is the worst thing to have in the oil, because it goes everywhere as it is suspended completely in the oil. I'd rather have a handful of metal chunks in the oil as a pinch of ferromagnetic dust.
I learned all of this the hard way, by trying to resurrect engines in the old days when we first started IMSB development. All it took was one instance where my patch up didn't work to learn the proper corrective action, and exactly what should not be done. Knowing what not to do is more important than knowing what to do in these scenarios.
Judgment comes from experience, experience often comes from bad judgment.
Pull the sump plate and you'll find more material, clean it a dozen times and dropping a cow magnet into the sump isn't a bad idea, either.
Remember, for ANY MATERIAL TO MAKE IT INTO THE FILTER IT MUST PASS THROUGH THE OIL PUMP FIRST!
So all that debris thats in the filter, yep, it has taken oil pump clearance with it. Don't be surprised if come July and hot ambient temps the oil pressure light doesn't flicker at idle, because just enough pump material has been compromised to open clearance and create a low oil pressure issue. We see this all the time.