Well. I dug out the lease document and things aren't quite as bad as I feared. It is, indeed, closer to the 9K end not the 10K end. And I'd forgotten about some tax refunds owed to us. So the revised numbers look more like this.
Current: 4200 on the LoC and 400 per month payments.
May 2008: Car gets added to LoC taking it to 11400 (Our LoC is an excellent interest rate, it's as good a place as any to borrow 9K from. I dont think I can get a 0% interest card with that kind of limit) Car payments get added to LoC payments bringing the per month up to 750 per month.
Sometime between now and then: 1200 dollars comes back to us as a refund from the govt. Which takes the loan down to 10200. 750 a month for the rest of 2008 leaves a 4200 debt at the end of 2008. Or about 323 a month over what we pay currently. (including December). This.. this is doable. I think. :) Another post will be crunching the budget numbers to see just how doable this really is.