convert factory KC4 oil cooler lines to -AN lines 1990 k1500

[droptail]

I upgraded my radiator which now doesn't have a built-in engine oil cooler.
Is circulation required to go through the factory oil cooler lines (if cooler removed)?  They can't be capped, only bypassed(looped) to keep circulation - correct?

 

Anyone convert factory KC4 oil cooler lines to -AN lines on a '90 5.7 k1500? 
What size are the ports on the engine block cooler adapter so I can use an -AN adapter? 

 

thanks

Edited August 19, 2019 by droptail