Is it possible to update my Hackintosh to Mojave, or will I have to start again from scratch as with a newly built machine?

I built my Hackintosh 3 years ago, it's currently running El Capitan but it's finally becoming a problem to run such an old OS and I'm being reluctantly forced to update. I realise now though, that I'm pretty rusty on the whole Hackintosh thing since it worked when I set it up and I never really had to worry much about it since.

My rig is as follows:

I initially tried to bite the bullet and see what would happen just updating from the AppStore as with a real mac and realised that it wouldn't work because I had had to set my SMBIOS up such that it says I'm running a MacPro 3,1 from 2008. I changed this to the 2013 model, assuming it'd break a few things, but I could worry about those after the update, except it actually completely borked the whole system and it refused to boot. So I had to recover my old config.plist and fix the SMBIOS entry and go back to how things were.

Now I'm wondering if maybe I'm being a bit gung-ho on this, perhaps there's more to consider. Is it actually possible for me to just update this hackintosh or will I have to create a bootable USB installer like I did the first time around, and all of that difficult finnickyness with very carefully changing hundreds of variables until it all works? What's the general experience with Mojave on Hackintoshes? Is it working mostly well?

What most concerns me is my Graphics card because I'll need that to continue working or the system will be near useless with nothing but the intergraded GPU. Can I still run web drivers from NVIDIA?

Are there any guides for updating? I've found a reddit thread for installing from scratch https://www.reddit.com/r/hackintosh/comments/at96il/process_to_install_hackintosh_mojave_on_z390_and/ but I rather hoped it'd be different/easier to update.