| Boycey,
In the very early 70's (straight after being at Brize Norton) I used to look after the Indian Air Force AN-12's when they dropped into Sharjah (just outside Dubai) for a refuel, cleanout and watering.
Basically, all they used to have when in PAX role, would be very basic aluminium tube and webbing seating, laid out in rows across the fuselage. If in freight layout, they would utilise a gantry crane built into the upper fuselage to lift cargo from just under the tailplane and position it anywhere on the cargo bearing floor. I never saw one fitted with side guidance for parachute cargo drop, but I suppose it could easily have been fitted, because all the heavy mounting points were built into the floor.
One thing I was always amazed at, was seeing a cargo aircraft fitted with nose and tail guns, plus how flimsy the undercarriage was, it just looked like a spiders web of thin tubing welded up to support the main oleo strut, as people walked about inside the aircraft, you could see it all flexing.
Maybe if you get stuck on obtaining info and photos, look at other air forces that used the same aircraft.
John | 
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