How to properly install OpenWrt on Asus RT-AC58U?

Thank you for replying to me. I tried doing exactly what you posted but couldn't get it to work. However thanks to giving me something to work with I was able to copy the files doing it the following way. I kept it default port 22 and I just type
scp admin@192.168.50.1:/temp/ubi0_1 ~/Downloads/

that allowed me to copy the file. But then I read your comment on enabling the wifi. I'm new to openwrt, I have used dd-wrt before though. I think I might have been fine the first time I did it if I just enabled the wifi, which was stupid of me. I might not of even needed to save those files.

Which brings me to another question for anyone who sees this. What do you do with those saved files (ubi0_1 and ubi0_2)? Do they need to be uploaded back to the router now? Currently in the wireless overview the router list a Generic radio 0 and radio 1 and the 2 wifi ssid that I created for the 2.4 channel and 5.0 channel. Everything seems to be working so I'm wondering what I should do with the 2 files I saved to my Mac.

Again thank you for your help