Upgrade install: Only add the lines after and including [MiniAmmoDisplay] to HUD.ini
New install: Add all of the following to HUD.ini

[MiniHealthDisplay]
Enabled = true
Background.Width = 72
Background.Height = 30
Background.Texture.File = d6hud_ext.tga
;Background.Texture.Quad.Left = 0	; default value is 0
;Background.Texture.Quad.Top = 0	; default value is 0
;Background.Texture.Quad.Right = 72	; default value is Background.Texture.Quad.Left + Background.Width
;Background.Texture.Quad.Bottom = 30	; default value is Background.Texture.Quad.Top  + Background.Height
Background.Position.Centered = true
Background.Position.X = -200.0
Background.Position.Y = 0
Text.Font.File = font18x24bankgoth.tga
Text.Font.AverageCharacterHeight = 14
Text.Position.X = -212.0
ForceInfoDisplayDuringLowHealth = true
LowHealthThreshold = 50.0
HealthInfoFlashDuration = 2000 ; aka 2 seconds
LowHealthBlinkDuration = 250 ; aka 0.25 seconds

[MiniAmmoDisplay]
Enabled = true
Background.Width = 72
Background.Height = 30
Background.Texture.File = d6hud_ext.tga
;Background.Texture.Quad.Left = 0			; default value is 0
Background.Texture.Quad.Top = 31			; default value is 0
;Background.Texture.Quad.Right = 72			; default value is Background.Texture.Quad.Left + Background.Width
;Background.Texture.Quad.Bottom = 30		; default value is Background.Texture.Quad.Top  + Background.Height

Background.Position.Centered = true
Background.Position.X = 200.0
Background.Position.Y = 0

Text.Font.File = font18x24bankgoth.tga
Text.Font.AverageCharacterHeight = 14
Text.Position.X = 192.0

AmmoInfoFlashDuration = 2000 ; aka 2 seconds