Please remember there is a shim behind the circlip to take the endplay out - i don't see it being replaced - so mostlikely its been lost ?
it sits on the plate behind the circlip and is easily not seen - but its very important as it stops the driveshaft chattering - as yours seems to be very tight it may be ok - but of all the ones i have ever done on all the Isuzu's - i have never had a tight circlip like yours - except once ! - and that was from another owner having your problem - it turned out to be the outer race from the inner bearing not being seated tight in the hub
regards
Steve