urban myth or heartbreak hotel?

Ok, this is totally non-medical but it is the weekend, and this is important stuff. I have it on good authority (pop culture junky and guru who lives across the road) that Elvis was a natural blonde. A quick flick on google at least repeats the claim, albeit on a website called suicidegirls, saying that Elvis dyed his sandy blonde hair black.
Any further light on the hue of Elvis's locks would be appreciated.