I love this thread, because it sounds like something I'd think of!
I think you have a couple of issues here, most of which have already been mentioned. Be sure to factor in eBay fees, and PayPal fees. Shipping costs will also add up.
I did this math on parting out out old G35 at a buyback of something like $700, and couldn't make the numbers work comfortably... At least for parts I could pull and ship easily. I can't imagine covering $8000 with interest and monthly payments.
If you like the car, I'd drive it.