Resetting Router to out of the box settings

Trying to figure out how to reset the router to how it was out of the box. I tried option (1) from the unbricking instructions by flashing with the openwrt-ramips-mt7620-wr8305rt-squashfs-sysupgrade.bin. It did not work. So I got lazy, and thought that if I downloaded the other firmware, flashdump.bin , for option (2) and used the same procedures I used in option (1) it would work. Turns out, it did not. It still boots up, it still shows up as root, and typing has been a pain. I can’t even type any complete commands. For example if i would just type “id” only the “i” shows up on screen. I figured to do it the right way this time using option (2). But here’s my dilemma now, i could not remember if need to use Tigard or Bitmagic to do it. I figured since BitMagic is a logic analyzer, that won’t be the device to use. So if I went with Tigard, which wiring harness to use, i don’t believe it’ll be the JTAG or the UART connector that came with the Tigard package. I’m guessing its the BitMagic harness. I am just not sure where to connect it. Thanks in advance for the assist.