Eramus

If anyone can help would be appreciated....... I recently bought a new 4080 gpu and a thermaltake core x71 series case. My issue is ive tried contacting thermaltake, and a few suppliers but no one can answer me 100%. Im trying to mount the gpu vertically but the supplied gpu mount does not fit any way with the 4080 (display ports dont line up) out by about 5mm. I dont want too have to cut into the case can i use a compatible mount from nzxt or cooler master for example????? Any help would be greatly appreciated.