I have a similiar set up with my Parasound A-51 amp, its in a Standout design wood AV cabinet. Its open to the front, and has minimal side clearance, and it runs warm. I also use it as 5 channel amp for my HT rears and center, and have it with long cable runs to my zone 2 outdoor speakers. It's been a reliable workhorse for over 4 years with this set up, and I've had no problems at all with overheating, or having safety therms kick off. Don't open the cover, but you may want to drill larger openings in the back the promote more air flow. I've not needed any cooling fans. I also use the Marantz 7005 for HT and am very pleased with this combo. Good luck, you shouldn't have to worry, just enjoy with a few simple modifications.
Good luck,
Bob
Good luck,
Bob