carpet dyeing free carpet for duster

We are going from the gold to black. Last night when I checked a corner of it, it was looking dark green. I was hoping by leaving it in at least all night it would help to darken it up more. The carpet is the original 1973 carpet so I'm guessing it's the 80/20. I was really Gung ho and optimistic when I saw the video results of someone else trying it out. But not sure when I saw it dark green. The car is a full resto mod, so we had planned on just buying new carpet for it originally. But thought if we could make the one I got free work for a few bucks it would be great. If not, then just stick with the plan to buy new. Nothing ventured, nothing gained. Lol.