OK, I've decided to replace my leaky radiator and since I have an
automatic transmission, there are two oil cooler lines I need to
disconnect, which seems easy to do.  But I read that I need to
"transfer oil cooler line connectors to new radiator using pipe sealant
with suitable oil resistant sealer".

So these "connectors", do they just unscrew from the old radiator?  I
assume they sell this "pipe sealant" and "oil resistant sealer" at the
auto parts store, but I'm not sure where to apply each.

Can anyone elaborate on this?