Removing cigarette tar from chassis

[Adam]

I have cleaned a really gooked up chassis like that with laquer thinner. But I didn't just pour it on the chassis, I used a rag with the laquer thinner on it, or a brush (small paint brush, tooth brush, ...) dipped in the laquer thinner, so I could keep it away from more sensitive parts. And I'm talking about using laquer thinner specifically, not paint thinner. So for really bad sticky cigarette gook, I have resorted to laquer thinner and it worked ok. Although I don't know if I would recommend it given how powerful of a solvent it is, I'd try the rubbing alchohol or one of those other products first.