On my 92 w/3.1, there is a metal fitting/elbow/piping is coming from the intake manifold, under the thermostat housing. It splits the water flow into 3 paths. 2 nipples to function as the TB warming loop, and a hard pipe running to the heater valve by the right fender. This is different than all of the other TB bypass threads I have seen, probably because a 3.1 was only a 2 or 3 year run in thirdgens.

If looking to delete it altogether to get rid of the TB coolant loop, and run a line from the intake manifold directly to the heater valve, here's your ticket. I've seen someone on here do it with Earl's fittings, but that will set you back at least $40 (cheapest I could find, on anplumbing.com for reference) for a couple little fittings. Also, anodized pieces feel out of place on the car to me.

For future search reference, a brass 1/2" npt male to 5/8" hose barb adapter is what is needed to bypass this with about a foot of 5/8" heater hose connecting a small section of the old metal line (which was cut behind the alternator) to the barb. I've also seen the adapter in stainless steel and chrome. I wouldn't hesitate to use stainless steel either.

Hope it helps someone in the future that is strapped for time, cash, or both!

 

Nevermind, found what I needed by hacking it out of there anyway to get a look at the thread size.

See O.P. for solution