Remove black tar patch

I have a 8 person Clearwater hot tub the previouis owner thought he had a leak in the back of the seat inside the tub. It turned out to be a scratch mark but they didn't remove the tar does anyone know if I can paint the tar patch too have it match the colour of the tub. What would you suggest I can use I did try taking it off but it also pulls of the fiberglass coating not good. I would appriciate any help you could offer to resolve this issue.:confused:

So is this inside the tub on the acrylic surface? I am confused about it pulling up the fiberglass. We have a citrus based surface cleaner that may work. I am leary to suggest any type of tar removal that you would use on say a car because I don't want your acrylic to be damaged.