Every part, reservoir or gallery that supplies, returns or needs oil, needs to thoroughly cleaned, the oil pump should be replaced.
The crank should be split, examined and spotlessly cleaned, before and after you have it reground. The head needs to have it's rocker spindles removed, same for valves; the springs can hide destructive particles.
The oil tank should be removed and cleaned. Bearings should get binned. Cam and followers examined carefully.
The process isn't pleasant or inexpensive. The last time I blew up an engine I was so disgusted with myself I didn't even look at it for over a year; I had no one to blame, but myself. Not saying that anyone else's blown engine was the their fault.
Anyone who goes through this drama has my sympathy, except the cheap bastards that rebuild light bulbs...
Best wishes brother