I tried to edit it and there is no option to add GIN. I found the phone number to Listia but all I got was a recording. Maybe if you're the only bidder I could just relist it again with a GIN for 500 credits & free shipping, I can email you my phone number right before I select submit, then you can call me and have Listia on your computer so you can choose GIN as soon as it posts. Email me as soon as you get this and let me know if this will work or if you can come up with a better solution.
I don't know how you can remove the bid. I tried to remove one before when I accidently bid on something but I couldn't. I guess we'll just have to wait till it's over and hope that nobody else bids on it.