“drm:[drm_crtc_helper_set_config] *ERROR* failed to set mode on [CRTC6]” during install

Talking straight away, copy pasting the error as found and seen via terminal in search engines the solution might haunt peeps of all genres, here’s a perfect hunt down for the same.

Solution in short: Have you tried adding the kernel option/parameter nomodeset when you boot your install media?

BTW, you are not using multiple monitors, are you? If so, then perhaps try disconnecting all but one of them during the install? (He’s been there, done that. No joy.)

Explanation: You need to do this Joe !

The main thing this page appears to provide is an easy way to allow you to boot with common kernel options applied. You press the F6 key and use the space bar to select/unselect the option(s) you want to apply and then resume the boot. 

3 kernel options selected with F6

(By the way, have you already tried booting with the nomodeset kernel option? It seems to be a popular recommendation whenever video may be the problem.)

That’s it, have fun troubleshooting.