I know, I'm a little confused, too. Only happens when running. It's definitely PSF. If I had a YT account I'd post video. It's a pretty steady stream. Wild.Don't see how the box could transfer the fluid through the rag joint & steering shaft.
There is/was grease in that joint, Probably separated & is leaking out the boot.
A leaking input seal will blow fluid everywhere...But the rag joint will be soaked.
I'll probably disconnect at the input shaft and slide the shaft back, at which point it should be coming from the input seal.