I would recommend you flash the sysupgrade image as it easier and keeps the continued use of GL-iNets GUI UBoot.
MT-2500/MT-3000/MT-6000 (solidus1983.duckdns.org).
Direct link to image you need: https://openwrt.solidus1983.duckdns.org/snapshots/r24673/targets/mediatek/filogic/openwrt-mediatek-filogic-glinet_gl-mt6000-squashfs-sysupgrade.bin
If you ever have used the AX1800 and AXT1800 builds i have made and still do then this image is no different.