[Elecraft] K3 Sub Receiver Aux Antenna Input Option

[Harry Yingst via Elecraft]

I was looking through the Installation manual for the Sub Receiver and saw that I need to decide which aux antenna Option to use either the deselected antenna on the KAT3 or the dedicated BNC Input.
Note: I'm planning to put up a 25' vertical whip as a dedicated RX antenna

I'm leaning towards the deselected antenna because I plan to add the KPA500 and use the Ant 1 output to feed into the amplifier I would then  connect the RX antenna to the antenna 2 position
This would also leave me an open hole on the back of the radio to route out the IF from the second RX.

Thoughts?