It's my understanding that Back to Black is meant for plastic and rubber trim, and not for painted surfaces. The automotive detailing product is meant to cover up sun-faded plastics and I certainly would never use it on any of my typewriters, especially not on the platen or feed rollers. I've also heard that the "protective finish" is a real dust magnet.

A product recommended earlier in this thread that I would strongly recommend passing by is "Scrubbing Bubbles". It softens paint and destroys the finish of plastic, and that yucky looking color you see bubbling up which gives you the warm feeling you are removing years of built up cigarette smoke is more likely dissolved finish! Avoid this stuff.

I have learned my lesson and for cleaning the exterior I will now stick to water + mild detergent, at most.

Wrinkle (crinkle) paint cleaning techniques have been discussed in a number of threads here in the past, but I think this one covers it fairly well: http://typewriter.boardhost.com/viewtopic.php?id=1260

I agree with Repartee and Valiant that mild soap and water is often all that's needed. I personally use a degreasing household cleaner that is safe on paint - sparingly - and find that does a great job. You have to be patient and makes sure to gently clean in every direction to get it really clean. Vigorous scrubbing and harsh chemicals are to be avoided at all costs.