More arc problems

[Half Track]

Hi everyone.
I am trying to make a round open topped bunker that consists of a base(to raise above the enemy shots), on this is a circular wall and on top of this are three arced pillars supporting another circular wall on top.
Could anyone point out how I position the second two pillars?

Below is the bunker with the two pillars missing. I would like the pillars equidistant (not asking for much am I!!! lol). Seriously though, any help would be appreciated!

Code:
arc
name bunker_base
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 1 # (outrad - inrad) / outrad
position 0.0 0.0 0.0
size 20 20 0.25
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_lower_wall
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 0.25
size 20 20 1.5
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_pillar_1
divisions 1 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 12 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 1.75
size 20 20 1.0
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_upper_wall
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 2.75
size 20 20 4.5
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

[Half Track]

After th 101st experiment I got it!!

Code below for anyone like me who struggles with these things:

arc
name bunker_base
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 1 # (outrad - inrad) / outrad
position 0.0 0.0 0.0
size 20 20 0.25
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_lower_wall
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 0.25
size 20 20 1.5
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_pillar_1
divisions 1 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 12 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 1.75
size 20 20 1.0
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end

arc
name bunker_pillar_2
divisions 1 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 12 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 1.75
size 20 20 1.0
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
spin 120 0 0 1
smoothbounce # ricochets use normals
end

arc
name bunker_pillar_3
divisions 1 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 12 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 1.75
size 20 20 1.0
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
spin 240 0 0 1
smoothbounce # ricochets use normals
end

arc
name bunker_upper_wall
divisions 48 # number of subdivisions
flatshading # flat shading (smooth is default)
angle 360 # the sweep angle
ratio 0.10 # (outrad - inrad) / outrad
position 0.0 0.0 2.75
size 20 20 4.5
rotation 0.0
shift 0 0 0 # (repeatable)
scale 1 1 1 # (repeatable)
shear 0 0 0 # (repeatable)
smoothbounce # ricochets use normals
end