S2martin

I have a vauxhall chav-alier as my work shit box and the other day the cooling fan seized while sitting in traffic,
So instead of buying another fan i thought i'll sling my cossie fans on that are sitting in my workshop gathering dust to save a few quid,
Now i got the fookers in with a little bit of persuasion and swearing but
as they are a twin fan instead of a single (i spend my life in traffic on the A406 and A13 every day ), I thought it would be better with the 2 fans but the fusebox don't really like the draw they give so it blows the fuse after 10 mins,as the cossie fans wiring is 3 x thicker than the chav-alier ones so i want to just run a fused positive wire from battery to a switch in the car back to fans but am unsure as to what gauge wire to use????

Any ideas anyone?

Thanks
Martin