How do I replace a single
Color in photoshop!?
All, and I really mean all, sites I find with Google either use the replace color tool box (which just replaces hue), the replace color tool (which just replaces hue and saturation), or use color adjustment layers, colorize, gradient layers, select color range, etc which all modify a (fussy) range of colors and can't be applied on a specific part of an image without going through extra trouble (layers).
I just want to quickly replace a single color, (eg. red 255,0,0,0) with another color (eg. Green 0,255,0), and do this often because I work with pixel art most of the time.
To illustrate it with Paint Shop Pro, this is what I want: