I’ve been away from L1T for quite some time and i return, as it should be, with a Linxu Question 
I’m in the process of finally getting around to giving Gentoo a try on my main machine. I’ve done the basic Setup with the desktop/gnome/systemd Profile. I didn’t change any USE Flags so far (expcept adding nvidia for my GPU) and went through the Kernel Config pretty roughly, mostly keeping the defaults and just excluding the Intel stuff i don’t need.
I did it like this to get a booting system first. Now that that’s done, i’d like to start optimzing things a bit. I’m pretty sure i’ve get the USE Flags down. I know how to make changes and how to recompile my system to reflect those changes. No issue there.
But now on to the kernel side. What is the intended/recommended way of having multiple versions of the same Kernel Version available? I’d like to make changes and try different things, but keep the currently booting kernel as a fallback/backup option.
I know, so far, that i’d have to have two compiled kernels and initramfs in /boot and reconfigure grub afterwards. But, wouldn recompiling the kernel with different options just overwrite my current Kernel since they are the same Version?
Can i just rename the current Kernel and Initramfs files to something-fallbank and the compile a new version?
So yeah, what is the Gentoo “recommendet” way of managing multiple Kernels? Also, am i able to have more than one Kernel Configuration available? So i can keep track of varying changes i made over a period of time?