'99 LA1 has NUT,FRT WHL DRV SHF(M24X2.0X19.6)(HEX W/WASHER,PREVAILING TORQUE)
#13
If the slave cylinder is leaking you probably won't see it, but your clutch and bellhousing will be swimming in brakefluid.
Or if the slave cylinder is outside, see if the refilling it, and using the clutch, works at the slave, if not then your prob lays somewhere "upstream"