Receiver Ventilation - Minimal Clearance On Top :(

So we finally found ourselves in a position (wife and I) to upgrade our home theater sound system to better match our 65" Panny Plasma.

The problem I'm facing is I finally picked out the perfect receiver to go with the Aperion Audio Verus Forte surround speakers and SVS PB12-NSD sub, and it probably won't work in the space I have.

If I were to get the Onkyo TX-NR818, I would only have about 1/4" free space on top of the receiver, 1" on each side, and completely open front and back. That 1/4" is probably no where near enough for proper ventilation even with the open front and back. Please tell me I can get away with it if at all possible. If not the backup receiver I picked is the Denon 3313CI which is shorter, but that doesn't have the Audyssey XT32 feature I so desire.

I have the option of drilling ventilation holes in the wooden shelf above the unit but the cable box sits on that shelf and doesn't sit very high off the shelf itself.

Is the XT32 really worth me pulling my hair out over this? Getting a new unit isn't really feasible as I had this one custom made and I really really want to keep it.

Any advice you guys can give would be appreciated. LOVE this site and have been researching things here for quite a few years. I believe this is my first post.

Unfortunately that's the only space I have to work with. I'll definitely look into the pioneer as well. Most of the other receivers I've considered are only 6.5" which should work. The onkyo is almost 8" tall.

Denon AVR-4311. Audyssey XT-32 and only 6.7" tall. That should work nicely. I am replacing the Denon AVR-591 that came with the Boston Acoustic speakers that is the same size. No ventilation issues now at all with the open front and back. It's close to the floor of the sub level so it's always cool there as it is. I know the new receiver is more powerful but it shouldn't be an issue. Nice to have the 9.2 to give us the option of running another zone when we finally leave NY and get a bigger place.

Thoughts?

I had considered a new cabinet but every one I have seen all have the same problem. The space between the shelves give no where near the recommended space above the receiver.

This is what I'm working with.