So, I sent an e-mail to my new boss last night asking for a higher starting wage. I was very diplomatic about it and explained my reasons without being demanding or rude. I talked to him today, and the answer is no.
However, I'm not upset about it. I have made it abundantly clear to him that I'm not too impressed with the wage, and that I know the previous employee was making a lot more. Up to yesterday, he had been saying "Well, give me 7 months to a year, and I'll make sure you get a raise." Today, after my wage-mongering, he says, "Three to 6 months." That works for me.
I start training tomorrow, and should take over fully on Monday 1st. Or something.