LT230 PIECE OF STEEL ON MAGNET

Hi all, new to forum.
Looking for some advice,
Recently replaced clutch, upon test drive I stopped to test diff lock, at that moment the TC jammed, and eventually with a bit of load, "banged" into moving again.
I then drained TC oil and found a chunk of steel on sump plug magnet.
Anyone recognize what this may be??

I did not do any work to TC other than replace outer seals.

I have seen a thread (#bossman) where he mentioned that his LT230 was "stuck" landed up saying that he had put the wrong bolt in the wrong hole (TC to gearbox) and the bolt touched a gear??

I am assuming I have done the same thing.

Even though this bit of steel found on magnet, still drives and sounds as it should, selects high and low, difflock works fine, but obviously something needs to be repaired.

Any advise would be appreciated