After a research, The stunts were used actually for the exploding guns where clearly we can see the soldiers moving carefully and also some of them being hit by the explosion. (This scene also used the bulbs)
The bulbs were tested with locals (Who played the soldiers in closeups shooted in January 1981,who included the beam hitting the cameraman and the soldier hitted in his eyes and hands ) so i guess they weren't stunts but the bulbs were controlled by special effects technicians who also played soldiers in the scene (ex. Trevor Butterfield who opened the ark).
Changing the subject (Because this is not the thread) I will talk about when I saw the Opening of the ark the first time in my life, I saw a totally different thing:
1.All the ghost were angels like the skull one.
2. Actually all the ghosts turned into skeletons.
3. I remember Belloq scared when he said "It's Beautiful"
4. I remember also shots of the soldiers dancing in the fog.
5. Marion and Indy stake was in the ground with the soldiers, not in a elevated place.
6.I remember the shot where Belloq was covered in fire like a very scare scene and as a closeup of Belloq, not a general shot including Dietrich and Toht (With belloq in agony).
7.I remember shots of the soldiers reacting to Belloq Fire.
8.Belloq was throwing the beams.
9.Some soldiers were hitted by beams, after that, the antagonist trio dies, after that the soldiers dies.
10.The soldier chest bright was purple o pink.
11.Belloq was not screaming before his death, only Toht and Dietrich.
12. Dietrich death was very different: his mouth enlarged like in the movie, his eyes rolled up like in the movie, his nose falled and his cheeks and chins fell in pieces. also his head shrinks like in the movie but also melts like toht (without reaching the skull).
13. Toht death was not very different but some of his faces features falled in solid pieces, more than liquid. also the glasses falled to the ground, not the neck.
14. Belloq death was also different and longer: after killing all the soldiers, the fire consumed belloq until the point of his head evaporating and his headless body exploding and his arms detaching of the body, but the fire only showed Belloq's shadow death, after that the fire dissapears.
15.After belloq death as I said in point 9, the soldiers slowly falled to the ground collapsing, during that we can see that the bodies of Toht, Dietrich and Belloq dissapeared, instead we can see the ark being covered in a gold light that the soldiers are watching while they falled to the ground, then the light dissapeared, we see shots of the soldiers body (Not dummies, actually actor lying in the ground) before the bodies dissapears, then the column of fire rising up scenes plays as normal.
16. The scene begin with Belloq opening the ark, then instead of the sand scene, we see a bright light covering the altar and a noise, after we can see a reaction closeup of Toht, after, we can see closeups of the soldiers reacting, after that the lights blew up (including a focus operated by a soldier located on a cliff) in a different way that the movie but ending with the explosion of the generator, angelical choirs sounds as the fog appears in front of a scared Belloq, before the first ghost appear, we can see a ghost with the shape of a rat (like Bantu Wind hold) crossing the Tabernacle, then a ghost appears behind the soldiers, with more appearing.
17. Indy says to Marion to close her eyes before the opening of the ark.
18. Belloq prayer was longer.
Other misconceptions in Raiders:
1. Eaton doesn't had moustache.
2. Satipo corpse was half descomposed whe Indy found it (less than Forrestal)
3. Barranca back was bloodier
Also I remember different the death of Donovan to the movie one:
1.Donovan reaction to the cup was a nervous reaction segue to Donovan holding his neck, followed of reaction shots of Indy and Elsa.
2.then Donovan says his line of the movie "What is happening to me" but instead of the initial aged Donovan we can see a Normal donovan with his hand turning gray.
3. the shot of growing hair was longer.
4.Instead of "Doc Brown mummy " Donovan, I saw a gray skin Donovan with long hair and black clothes played by Glover, then his face fades (rather to morphing) to skull, point where the score intesifies .
5. Donovan skeleton gets mad (Running and screaming) while descomposing revealing a red chest.
6. Donovan isn't hitted by Indy, instead he is broken in pieces and falls to a cliff (The only part that doesn't fall is the skull)
There are more misconception of when I saw the trilogy but I think this post is long