abu 6500 handle question

hi lads just reassembling an abu 6500 multiplier.just wondering can anyone out there tell me how tight the nut holding on the handle needs to be (i.e. hand tight or spanner tight).i know the threads on these things have been known to get damaged so im a bit unsure myself .does anyone know? thanks
noel.

Just a LITTLE nip with spanner till the locking plate lines up with threaded hole.

cheers paul job done.