Yep that's what I meant. I got lucky eventually, up and running!
Used this, works out of the box with a few configs needed.
ASIX Electronics Corp. AX88179 Gigabit Ethernet
1. ssh in
2. execute:
ifconfig eth1 up
2. use nano (for example):
nano /etc/config/network
and append this to the end of the file:
config interface 'wan'
option ifname 'eth1'
option proto 'dhcp'
config interface 'wan6'
option ifname 'eth1'
option proto 'dhcpv6'
3. Execute:
service network reload
4. Verify with (for example):
ping 8.8.8.8
and also Advanced > Look for Upgrade will work now, as will Modules > Manage Modules > Get Modules From Hak5 Community Repositories.
References: https://openwrt.org/docs/guide-user/network/ucicheatsheet, https://openwrt.org/docs/guide-user/base-system/basic-networking