i didn't.. but then i thought about it and it occurred to me that i could just use the existing wall plate by the TV to send the speaker cable down.

so that would mean having to cut out only one more spot on the other wall for a new plate, which would be easy to patch if i ever wanted.

i just hadn't thought it through, but this should work out very nicely. i'll get to it one day.

the 4 post plate you linked will work fine for the rear, but i'll need a 6 keystone plate for the front since i still need the spot for the coax.