Its usually the little white cup looking thing on the firewall usually right beside the brake mastercylinder. Its actually called a slave cylinder thats probably giving you the problem and it mounted on the clutch housing, I beleive, but the reservoir to it is most likely on the firewall right close to the brake mastercylinder.
RED JEEP CLUB MEMBER #92
'92 WRANGLER, 2.5 Litre, 5 Speed, Rag Top, Superwinch LP8500, Cepek 130W Driving Lights, 31x10.50/AT with no lift, Of course! It rubs!