The P-47 has the option of only using 6 guns - the P-51D 4 guns and the P-40N 4 guns. The rule of thumb is to use standard factory equipment, yet these three planes differ from standard. The 190A5/A8 has the option to take 2 or 4 cannons. Since only 1 load out can be "standard", all these planes break the rules in a way. So, can we delete guns from other planes too?
Such as:
P-39D - 30 caliber delete
Mossie - 303 delete