Airport Extreme as wireless access point?

Hi,

I've searched the forums already and found some relevant threads that make it seem as though my potential configuration will in fact work as anticipated. But those posts are relatively old now and I want to list my specific (proposed) setup to make sure it's going to function as expected with the gear I have + the gear I'd buy.

First off my modem lives in a weatherproof box 700 feet from my house. The theory then is to put a Mikrotik hEX RB750Gr3 (wired) router in the box with the modem as well as an Enable-IT 821C Coax Ethernet Extender.

Then I'd run 700 feet of coaxial from one 821C to my house which would terminate in the other 821C “receiver.”  Then I'd hope to simply connect an ethernet cable to the coax extender in my house that would run to my Airport Extreme to serve wireless internet.

FWIW, I am mildly intimidated by the Mikrotik router because I have zero experience with it thus far. I'm considering it because it's a small, wired (only) router which appears to suit my needs—on paper. It seems to be highly configurable, however it sounds like it would be ready to go, with a basic setup onboard, right out of the box. Which would be terrific. But that's not the big question.

How do I configure my Airport Extreme in this situation? I haven't used it in 5 years because my current internet setup is something I "inherited" when I moved into a new property. But it's time to set up my own system now and bypass the existing setup in a different, more robust way.

With my previous Airport Extreme setup, in my previous house, it was simply: modem — Airport Extreme — done. By inserting this wired router in between the modem and my AE, what configuration should the AE take now?

Thanks in advance!