Found an old image on my hard drive that's been sitting since the days of Halo 3. I recall fooling around with exploring outside the multiplayer map 'Heretic' and seeing it from the outside. It was fun to pan-cam around the carrier and cruisers. Anyhoo, I was trying to find some architecture on the CCS-class cruiser hull that matched the size and general shape of the 'Heretic' map. I think I found the most likely contender (7 years ago) but had never posted the pic for some reason.

I don't think the gold-ish windows would be visible on the outside of the hull, in the same way as there are 1-way windows of that nature on 'Snowbound' and 'Assembly'.

Better late than never I guess. Here's my supposition of a probable location of the map in the cruiser: