I do not recommend a damp cloth on anything inside your PC
Ok I think I will go with what u say about the damp cloth and air compressor. Not saying it wouldn't work, more that I'm not an expert so keep it simple as possible.
Don't have a hose on my fancypants electric vacuum. Is touching the components with a duster/mitt etc unadvisable? Might have to take everything out I think.
Could u address the yellow wire issue?