I do a lot of media blasting in my business which is firearms refinishing. We do a lot of machine guns, automatic weapons plus sniper rifles used by NATO and others. The tolerances in some of these weapons are less than you would see in a race motor. You might say everything is in the prep work. If a truck part (let's say frame) is stripped, it is a very good way to remove everything getting it ready to paint. If someone wanted to blast an engine with all the stuff still hanging on it...no way. The best way to get a truck ready to paint is explode it. If you do that then blasting (the right kind of media of course) is my way to go. It's not a black art. Find someone you trust to do your blasting and they will know what can or can't be done.

Six volt guy living in a twelve volt world