You can use brake fluid but it typically doesn't get every bit off. Like hamz said your better off getting a new 1. By the time you buy the fluid and invest the time it will probably work out cheaper for you anyway.
I agree with Killer and everyone else its not practical. I did it once to a Losi Baja lid that I bought from Randy before I found a couple of unpaited ones. Only about 97% of the paint came off which was fine as I'll just use a basher body. It did take many hours however most of which was just soaking with Dot 4....much less scrubbing than dot 3. If you can buy a new one I would go that route.