Entropy Radiator question

[SilverGT3RS]

Happy Memorial Day everyone!

I have some questions I’m hoping someone can help me with on a LS swap Entropy radiator.

I have several empty holes in the back of the radiator. 1 has a brass plug with anode (I’m assuming) and then there’s what looks to be a 1/2” threaded port below the upper hose neck, and a 1/4” threaded hole above the upper rad hose neck. The 1/4” hole above the upper hose port is for the steam port? What is the 1/2” hole for?

On the drivers side, I have 2 threaded holes top and bottom. I’m unsure of the size.

I’m assuming the drivers side holes are for the transmission lines? They don’t seem to be NPT. Anyone know what I need for these holes as far as fittings?

Thanks in advance!