I started eating paleo/primal to treat my fibro and it absolutely works as long as I don't stray back into sugar-land or eat grains or legumes. For me it took only 3 days for the pains to end - a little longer for the fatigue - like a year. I am now 19 months primal. I also suffer from IBS and am currently trying an elimination diet to see if my troubles stem from fructose Malabsorption. I'm only on day 2 of this experiment. I'm eating nothing but meat/fish/eggs for 2 weeks.
It is VERY rare for a male to have fibromyalgia. Are you sure you have a correct diagnosis? Have you been tested for tender points and have been found to have at least 11 of the 18 points?