Here are the Listed body groups for each of the ranking jobs from Enlisted to VCMDR+. (Sub unit body groups will be listed in their personal handbooks).
What Enlisted Can Wear:
Skins
Helmet (only take off if palpatine is in the room or to check for BX's)
Helmet Attachments I (Except 2)
Helmet Attachments II (Except 2)
Hair
Only wear one Gun pouch, no double, either left or right
Backpack (except 2 and 3)
Chest (except 3)
Chest Attachments II (except 4)
What Enlisted Cannot Wear:
Cama
Chest Attachments I
Pauldron Base
Left and Right Pauldron
No Double pistols, hip or chest
What NCO's Can Wear:
Anything mentioned above for Enlisted
Helmet Attachments I 2
Helmet Attachments II 2
Cama
Chest 3
Chest Attachments I
Chest Attachments II 4
What NCO's Cannot Wear:
Pauldron Base
Left and Right Pauldron
No Double pistols, hip or chest
Back pack 2 and 3
What Officers Can Wear:
Anything mentioned above for Enlisted and NCOs
Double Pistols
Pauldron Base (except blue)
Pauldrons (Black Only)
BackPack 2
What Officers Cannot Wear:
Double Pauldrons (unless its the small pauldron on the right)
Blue or white pauldrons
Backpack 3
For VCMDR+, they can wear basically anything, no body groups are restricted for them, and only sub unit Leads and VCMDR+ can wear Commander Rank plates. Any further questions about bodygroups please ask a 501st Officer+.