Kernel Panic When Trying to Install OS X 10.5 or 10.6 on Mac Pro 3,1

I've got a Mac Pro 3,1 with 10.11.6 currently installed and I'm trying to get 10.5 or 10.6 installed on a separate drive to mess around with older software and what not, but I keep having issues trying to install either of them. I've bought three different install disks, and they all produce similar failed results. I have a 10.5 family pack disk, a 10.6 disk from a iLife, iWork, and OS X box set, and 10.5.4 gray install disk. I know that the 3,1 Mac Pro originally shipped with 10.5.1, but I did some digging around on the gray disk and found that it should be compatible with the 3,1.

When trying to install 10.5 with either disk from Finder, I get the first screen shot. If I restart and do nothing, my boot drive loads and nothing else happens. When trying to boot from either disk, I get the Apple logo on a gray background momentarily and then a kernel panic.

When trying to install 10.6 from Finder, I get the second screenshot and that's that. When trying to boot from the install disk, I get a kernel panic as like the other disks.

Lastly, I've tried running OSInstall.mpkg from the System/Installation/Packages directory on every disk, and get the error in the third screenshot.

I've tried pretty much everything I've found on other posts and forums, and nothing seems to work. I would appreciate any help I can get.