I'm not sure if dirty flash will work good for you, but you can try. I always use OpenGApps Nano and never used any other GApps.Yess your are the man ! So fully confirm, no setting lost ! :
1- wipe : cache + dalvik.
2- flash the same rom or the updated one.
3- flash the zip of gapps nano or BiTGApps / avoid nickgapps
4- wipe cache. -reboot.
** To not waste about a day on the gapps : Do not connect over a wifi having a Wireguard connection ! You will never be able to get the login page of google. Kill the wireguard of that router or simply run openvpn and all will pop up fine.
- tomorrow i guess i might spend the day on how to run / apply the safetypatch.
Do we just install magisk and do the Hide renaming.. or the safetynet pack file 1.1 or 1.2beta is needed ?
If you want to bypass safetynet check in my roms, just install latest Magisk canary and hide Magisk app using its settings. No other patches are required.