Designing for on-wall/near-wall speaker placement

[morbo]

I've been asked to build some speakers for some friends. They want a cheap ($200-300 CDN) set of speakers that can be used to with a low-cost reciever to watch TV and some DVDs. I am planning a vented floor standing design (Fb = ~ 22 - 26hz) using the TB 871 for the a mid-tweeter, and the Dayton 8" RS driver as a true woofer. Yes, I know there is a price/performance mismatch here, but the future owner is a bass nut and I'm hoping being able to cross lower will simplify the crossover design process. The source and amplification will not be high end, so I don't feel the need for a higher end driver. The goal here is an inexpensive, shielded fullrange system with high quality bass.

One of the stipulations on these speakers is that they stand flush one either side of a big 51" RPTV. This means that the back of the speaker will only be about 2-3" from the rear wall. Since the speaker is 15" deep, this means the drivers will be roughly 17-18" from the back wall.

My question is this: How does one design for on/near wall placement? I haven't seen many speakers designed this way, and I'm curious what effect it has on the bass response and what to shoot for when modelling such a speaker?