mike, (presume ya names mike

)
theres no rhyme or reason for any weight rod/line ,a friend of mikgee and myself uses an 8# for bugging and spiders its only personal choice and fatigue that decrees the use of lighter outfits , the only thing i will say is that when your bugging for grayling you generally hold the rod out at arms length and a heavier outfit will obviously tire your arm quicker but if you get into it you can always purchase another outfit in time for it ,so in short yes your 6# will do ,if you decide when your going let me know and if i can make it i will come down with you