On the cheap and willing to sacrifice the engine? ( not sure if something is wrong how this could hurt it more) If you are unwilling to R&R the head and NEED the engine to run NOW.
I'd remove the intake and exhaust manifolds and all spark plugs. Then fit an air compressor to one of the spark plug holes (screw-in fitting) and hand cycle the engine thru several rotations. That might blow out any remaining pieces from the chamber and any left on the valve surfaces.
Repeat for each cylinder.
What's the worse that can happen?
P.S. I've got nothing personally to lose....... Do you feel lucky? Well, do ya?
_________________
Chuck.
“Any suspension will work if you don’t let it.” - Colin Chapman
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