Bulkhead size for 1.75" hole?

[Hyphnx]

Just got my tank from Planet Aquarium and they have the drilled holes listed as 1.75" and then the overflow is 3x1.5". What size bulkhead would I need and for the returns? I am trying to find a 1" return.

Tank is a 310

 

[Cycleguy0623]

that would be a 1” bulkhead for sure. There is 1” modular hose it’s just harder to find I believe than 3/4