In-wall speaker wire to sub problems.

[Taipan]

Ok, so I'm almost done with my dedicated theater build, and I ran in-wall wiring for every speaker. I chose monoprice wire and speaker plates. I used a double pole post for the sub location and wired it. My sub can be wired by either a direct connected sub plug or the red/black connection. The master plate at the receiver end from monoprice only has a dedicated sub plug, and my receiver only has a direct connect for subs.

My question is: how do I use the inwall wiring for my sub with my current receiver?

Thanks for reading guys!