What are all the parts necessary to install A/C in 1990 Civic HB?

A/c Switch a/c Relay A/c compressor A/c compressor lines A/c condenser A/c condenser fan A/c High side lines 2 piece(inside bay) a/c Low side lines 2 piece(inside bay) A/c evap/dryer This is just common list and should have covered most if not all. this is just off my head. i might have missed some smaller things. You probably have r-12 system it would be wise to retrofit to r-134. r-12 is outdated and released into the atmosphere causes birth defects. lol r-12 is expensive stuff. uh maybe you should buy yourself a Haynes manual from your parts store it should have diagrams/parts/specs/removal and install procedures of the car.