As a cheat sheet, here's what I know so far has Gun Racks:
- 325a - 2 Primary - 3 Sidearm/Utility - 0 Heavy
- 400i - 6 Primary - 9 Sidearm/Utility - 0 Heavy
- 400i - 6 Primary - 9 Sidearm/Utility - 0 Heavy
- 890 Jump - 32 Primary - 0 Sidearm/Utility - 0 Heavy
- A2 - 16 Primary - 24 Sidearm/Utility - 4 Heavy
- Ballista - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- C2 - 16 Primary - 24 Sidearm/Utility - Heavy
- Carrack - 12 Primary - 0 Sidearm/Utility - 0 Heavy
- Centurian - 10 Primary - 0 Sidearm/Utility - 0 Heavy
- Constellation - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- Corsair - 6 Primary - 9 Sidearm/Utility - 2 Heavy
- Cutlass - 4 Primary - 0 Sidearm/Utility - 0 Heavy
- Cutlass Steel - 20 Primary (1 near each seat) - 0 Sidearm/Utility - 0 Heavy
- Cutter - 1 Primary - 3 Sidearm/Utility - 1 Heavy - 1 extra Utility
- Cyclone - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- Defender - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- Gladius - 2 Primary - 1 Sidearm/Utility - 0 Heavy - 2 Ammo?
- Inferno - 2 Primary - 1 Sidearm/Utility - 0 Heavy - 2 Ammo?
- M2 - 16 Primary - 24 Sidearm/Utility - 4 Heavy
- MSR - BUG Primary - BUG Sidearm/Utility - BUG Heavy
- Nomad - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- Scorpius - 2 Primary - 4 Sidearm/Utility - 0 Heavy
- STV - 2 Primary - 0 Sidearm/Utility - 0 Heavy
- Ursa - 4 Primary - 0 Sidearm/Utility - 0 Heavy
- Vulture - 2 Primary - 3 Sidearm/Utility - 0 Heavy