yup they'll work. i even believe that the gt's and cobras, maybe even 6ers all have the same rear brake setup. I looked at my 6 and took off the stock 15 and it fit right on the cobra. Nice lil show i put on. lol
I have 15x10 prostars on the back also. I had to grind the same bolt... But when you grind it. make sure you dont have any pads in the calipers. If you have pads, when they wear down, the caliper will move out, and you will get grinding again. I just recently found this out the hard way. I first put them on about 8mos ago. Car broke at the track and wheels sat in the garage. I got the car running after about 6mos downtime. And last thursday i put the prostars back on. They were fine until i hit the brakes, then they started grinding again. Again Make sure you remove the pads, so the caliper is at its lowest point when you grind the banjo bolt.