Sounds like you do it up right. I limit people getting inside to avoid liability and limit wear and tear on the vehicles, I’m the entire cleaning crew and getting all the greasy handprints off the outside is not fun.Late to the conversation.
The Cold War Collection's V100 was acquired mostly because it can be accessed easily by the public. Yes, the Collection has a very substantial liability insurance policy as a non-profit museum. The principal insists that the public can touch, smell and poke any of our vehicles. That includes the Ferret and CVRT. (That bit us in the arse only once when some little Christer stole a master key.)
The typical display includes myself as driver and my crew commander. The two master switches are shut off, the boat tank fuel supply is removed, and the wheels are chocked or sandbagged. The driver's seat is fully lowered. Personal items are removed, but not period-type artifacts like a steel helmet, a dinky pair of binos, a FAK, the extinguishers, some goggles, and the RT524 radio assembly. All doors, panels and hatches are opened.
One volunteer stands at one door, and the other is at the other side. On a timer, the group of kids or visitors inside are called out and the next batch enter. They rotate the cupola, sit in the seat, peer out the vision blocks. Mostly the visitors marvel at how simple and small it is. When not being inspected at finger-tip distance, I latch the bottom door sections or run a length of 550 cord between two magnets across the doorway.
I’m just not into running it like an amusement park ride, loading/unloading kids all day. When I run into Vietnam vets at the show, I want to spend my time talking to them, which leaves no one to monitor people entering the vehicle. Also, since I drive my vehicles to the show, I don’t want anyone inside touching/breaking things that could leave me stranded. I’ve also installed NOS seats, including the turret seat and I don’t want people standing on them. Then there are the VIC headsets and cords that would be easy meat for kids.
With regard to your kid-proofing the vehicle, I wouldn’t leave a charged fire extinguisher in there. I just upgraded mine to modern Halotron units and they are expensive. I’d be vexed if somebody triggered one. I’d also be worried about busy hands yanking the pull handle for the fire bottle.
Do you unplug the power cord for the radios? It’s not disabled by the factory kill switch. A prior owner of my vehicle let people get in his at a show and somebody turned the radios on. He had dead batteries at the end of the day and no slave cable.