So I cheated a little bit...

I installed using the usb boot method using Chameleon RC3... was having a video issues as well with my gtx 260. I had an extra video card laying around so I stuck that in and VOILA, it worked. Everything installed well, got Chameleon on my hdd and then I worked on the graphics card. Well long story short I got the card working.

Just follow pcwhiz's guide that is everything I did. I can help you if you need it.

Good luck!