Either way, I will backup the original abl_a and abl_b before flashing. It is really scary to brick a phone.good. Yes the best way, especially with korean rom, is to flash the v35 eng abl to your not active slot, which I think in your case is 'b', so abl_b.
the key to that working is you need to have twrp installed, so you can use it to set 'b' partition as active, then select 'reboot bootloader' and it will boot to fastboot. You can then use fastboot and follow the info in this vbmeta link. Read the directions.
the other option (if u don't have twrp yet), would be to flash v35 eng to a, boot to fastboot, do the vbmeta stuff, then use fastboot to flash the original abl_a back, so it will boot.
Thanks for your help again!!!!