On the TX-130 does Ammo take up an Arsenal Spot?

Example
Armor Piercing Shell
Tx-130 Beam Canon
Twin Lateral GA-6N Laser Cannons

Can I fire all 3 in one round?

If I fire the Lateral Laser Canons can I then fire the Tx-130 Beam at the same target? Would this be considered 2 suppressions or just 1 if there is a hit?

Ordnance is a weapon, therefore it counts toward a unit's Arsenal X limit.

If you want to fire both weapons at the same target, it has to be 1 Attack Pool with both weapons, and therefore 1 Suppression.

I would recommend taking another look at the steps for performing an attack in the Rules Reference Guide. It goes into forming attack pools and such.