OV-10A/D/D+ "Bronco"

Various weapon/fuel tanks combination, taken all from the available pictures

The info says that the 100gal underwing fuel tanks were only used on ferry flights to/from Gulf.
The most common load was 2 LAU-7/A adapters and one AIM-9L Sidewinder + fuel tanks/rocket pods on the fuselage/sponsons hardpoints.
There is also info about using SUU-25F/A flare pods with either LUU-2D/B flare with visible light or LUU-2B/B with IR light.
The flare pod looks like LAU-10 pod, more info HERE.

OV-10D+ (unknown BuNo., on the way to Gulf) (sand/brown/grey camouflage, sand/brown underwing tanks, grey centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  FPU-3/A
AERO 1C Fuel tank
150 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (BuNo.155494) (sand/brown/grey camouflage, sand/brown/grey underwing tanks, grey centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  FPU-3/A
AERO 1C Fuel tank
150 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (BuNo. 155483 and 155489, taking off of aircraft carrier, on the way to Gulf) (lizzard camouflage, lizzard camo underwing tanks + centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  FPU-3/A
AERO 1C Fuel tank
150 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (unknown BuNo. (probably UU-06), on the way to Gulf) (lizzard camouflage, lizzard camo underwing tanks, zinchromate primer centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  Fuel tank
230 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (BuNo. 155473, on the way to Gulf) (sand/brown/grey camouflage, sand/brown camo underwing tanks, grey centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  Fuel tank
230 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (BuNo. 155483) (lizzard camouflage, lizzard camo underwing tanks, grey centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  Fuel tank
230 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10D+ (BuNo. 155494) (superior grey camouflage, light grey underwing tanks, green centerline tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  FPU-3/A
AERO 1C Fuel tank
150 gal
  Fuel tank
100 gal
 Outer   Outer 
 Inner   Inner 

OV-10A (BuNo. 155428) (grey centerline fuel tank)

WingStub wingCenterStub wingWing
LAU-7/A  FPU-3/A
AERO 1C Fuel tank
150 gal
  LAU-7/A
AIM-9L
 OuterLAU-10
4 x WP rockets
 LAU-68D/AOuter 
 Inner   Inner 

OV-10D+ (BuNo. 155473) (sand/brown underwing fuel tanks, green centerline fuel tank)

WingStub wingCenterStub wingWing
Fuel tank
100 gal
  FPU-3/A
AERO 1C Fuel tank
150 gal
  Fuel tank
100 gal
 OuterLAU-10 LAU-68D/AOuter 
 Inner  LAU-68D/AInner 

OV-10D+ (BuNo. 155473) (green centerline fuel tank)

WingStub wingCenterStub wingWing
clean pylon  FPU-3/A
AERO 1C Fuel tank
150 gal
  LAU-7/A
AIM-9L
 OuterLAU-68D/A
7 x WP rockets
 LAU-10
4 x WP rockets
Outer 
 Inner   Inner 

OV-10D+ (from pic of BuNo. 155494, base tour for Vice President, Mr. Dan Quayle) (grey centerline fuel tank)

WingStub wingCenterStub wingWing
ADU-299 adapter
LAU-7/A
AIM-9M
  FPU-3/A
AERO 1C Fuel tank
150 gal
  ADU-299 adapter
LAU-7/A
AIM-9M
 OuterLAU-10
4 x WP rockets
 LAU-10
4 x WP rockets
Outer 
 Inner   Inner 

OV-10A (from Youtube video)

WingStub wingCenterStub wingWing
LAU-7/A  FPU-3/A
AERO 1C Fuel tank
150 gal
  LAU-7/A
 OuterLAU-10
4 x WP rockets
 LAU-10
4 x WP rockets
Outer 
 Inner   Inner 

OV-10D+ (info from Dan "Pigpen" Ahearn)

WingStub wingCenterStub wingWing
LAU-7/A  Fuel tank
230 gal
  LAU-7/A
AIM-9L
 OuterLAU-10
4 x WP rockets
 LAU-10
4 x WP rockets
Outer 
 InnerLAU-68D/A
7 x flare rockets
  Inner 

Info from Mr. Dave Ahearn, pilot who flew the Broncos in Gulf:
We (VMO-2) carried the M60's for a few days and quickly realized they were of no tactical value. They were difficult to arm and de-arm, so we took them out.
Weight was not really a consideration. We were typically above 15K, the M60 was of no benefit. VMO-1 flew with them as far as I know.
I recall we initially carried 2 Sidewinders, but the jet guys got a bit possesive and we settled on the one.