Perfect. Thanks, Booker! I had the hardest time coming up with effective search terms for this part; I'll be sure to use "intake" and "outlet" next time.
I think I'll try to develop the 'Gardena' quick-connect system talked about in that thread, and head down to Go-RV (I'm in North Van, so it's nice and close!) to see if I can't source the other hatches. Just need to nail down the LED light
replacements and it will be time to pull all the external hardware off the lower 1/3 of the trailer and paint
it with a think coating of truck-bed liner.
That is, if summer didn't end for the Lower Mainland last weekend...