GL-MT3000 NAT type B to NAT type A?

Please try to install attached ipk.
fullcone.ipk.zip (12.4 KB)
upload uncompressed ipk to MT3000 /tmp/ directory.
ipk source is from here.

Then install and enable fullcone NAT

opkg install /tmp/kmod-ipt-fullconenat_5.4.211+2022-02-13-108a36cb-10_aarch64_cortex-a53.ipk
opkg install /tmp/iptables-mod-fullconenat_2022-02-13-108a36cb-10_aarch64_cortex-a53.ipk
modprobe xt_FULLCONENAT
iptables -t nat -A zone_wan_prerouting -j FULLCONENAT
iptables -t nat -A zone_wan_postrouting -j FULLCONENAT

I failed to setup an environment to test it, please help.
and use snapshot 4.2 firmware please.