I was looking over the army book and the liz faq and didnt notice it mention if multiple skink characters could be on the same stegadon. It says they replace a crew member but I didnt see anywhere saying there could only be one hero per stegadon. Anyone know where to find the answer to this as perhaps I just glanced over it.
It's not mentioned in the book or the faq. However, I believe that it is not allowed. You could argue it out with your gaming club, but I wouldn't get my hopes up for it. You would never be able to do it at a tournament either. It would be nice if we could do that. I can see the war spear and another skink chief with fencer's blades. That would be awesome.
You dont buy heroes for your stegs, you buy a steg for your hero. No, you cant have more than one hero on a steg.
I agree with Arli, there isn't a rule anywhere that I know of and I even did a quick search in BRB. Skinklord also has a good point that you buy the steg for your character, not the character for a steg. You could try probably get a friendly game in with a willing participant in which you can play a Steg with multiple chiefs on it. I run a GM campaign in which I allow players to make creative units and other stuff that is outside the normal rules. It makes for great games when a player places a beautifully made Dwarven Zeplin on the field!