There are two types of brake systems on that year Chevy celebrity. Light duty and Heavy duty. the easiest way to tell them apart is the type of brake pads. The heavy duty brakes have a "butterfly" style retaining clip out the outboard pad that looks like wings when its not intalled. The light duty brakes have an outside pad that has tabs that must be tighened onto the caliper.
The type of brake system with vacum assist will have a large diameter hose from somewhere on the intake manifold to the brake booster. The type of brake system with hydro-boost will have hoses from the power steering pump to the brake booster.
DOT-3 brake fluid.
Look on the brake fluid reservoir cover, it should have the type of fluid required labeled on it. Most autos use dot 3 as I am sure your Impala does, unless it has a special brake system.
DOT 3
Dot 3
Dextron ii
a 2003 Chevy silverado taillight bulb uses a 3157
Regular DOT 3.
DOT 3 fluid
2002 model uses the 3057
DOT-3
Dot 3