Get yourself a Megs Clay Bar kit from Halfords, that should remove it. If it doesnt post up a pic/description of what you are trying to remove and we'll advise. Craig (Muddy) is an ex-pro detailler so he will know what to use to shift it safely
+1 But I'd avoid white spirit!
it will dry too quickly and leave a pattern in the chrome
after a wash they should be clean ? if not just use some polish on them to clean off any tarnished marks, then some wheel wax, i use poorboys