Infinity pistol really helps - also, are you using the pyro pete glitch ?
I will be on p.m 27 Dec 12 (UK time) - send invite to Hulio Geordio69 and I will walk you through it. Once you know the glitch (it's on YouTube), he is a piece of cake !!
Earlier today I solo'd him and he dropped 3 legendaries in one go - 2 grenades and a go faster slagger smg - his drop rate for legendaries is probably the highest of all the bosses - i reckon it's 1 in 10 !!
Lol, forgot about the glitch, cheers. Yes, the infinity pistol really helps, and I solo him with a shock and non elem 10.4 w/a sheriffs badge, but I don't have em right now. If you just want to beat him I could show you the glitch though