Twin Su Carbs... Canany One Help Plz

I'm restoring a mgbgt and it has twin su carbs.. it's a slow slightly neglected project but i have treated it to new points plugs and leads but having troubles with i presume the carbs.as it's got compressions a good spark and plenty of fuel getting to the carbs..

it's not wanting to start and the first 2 plugs are wet with fuel and the back 2 are black and sooty like it's running to rich.. all the floats seem to be ok and i was wondering if anyone had any clues on what the matter could be as there's nothing ovoiuse...

any ideas please help as i'm baffled...thanks jeff