I have a old mercury thermostat with 4 wires white on terminal w, red on terminal c , green on another c term. black on are term to be replaced by a rite temp model 6025 how do I wire ?

Can you go take a look inside the furnace cover and let me know what color wires are hooked to what terminals in there? This will be the easiest way for me to let you know how to wire your new stat. Also, let me know what teminals are on the new stat and we should be able to get this all wired up like it should be.