I have a roughly 6'x6' dead space on my second floor that was previously used to run exhaust pipes for my gas water heater and gas heater on the ground floor. This dead space currently has no access, but it would be handy to be able to get in there because it sits right above the breaker box, and I need to run a couple new electrical lines for a new on-demand water heater that will soon be installed.
The only place where building a door would be possible is in a small closet upstairs. The closet is a bit odd in that it's very short due to being against the roof line. It's like 4ft high at the most.
Since this will be very rarely used and almost never seen, the emphasis is on simplicity of installation and not looks. Is it possible to put some kind of door between the studs in the closet? I am NOT an experienced handyman, so something pre-built and/or simple is highly preferred.