I'd rotate the engine slowly until the intake valves were open. I'd then pull off the UIM/LIM. I'd then use some high pressure and blow air into the cylinder via the spark plug hole, and watch what came out the intake tracts.
You could also take some tack cloth, put on the end of a straightened hanger, and put that down into the spark plug hole and maneuver that around and see what sticks to it.
And like previously stated, a magnet part finder (I got one from AZ for like $3) into the hole as well to get any metal debris.
