I bought a 2000 taurus 3.0 flex fuel engine to replace my 2000 ranger 3.0 flex. I put new
head gaskets
and used the following parts from my ranger engine
Intake manifold
Oil pan
oil pump pickup tube.
Motor mounts
Exhaust manifolds
OIl pressure sending unit

Its all together and runs better than ever. This is a low cost solution because I couldnt find a ranger engine that wasnt worn out or over priced. The taurus 3.0 cost me $500 and shipped free (ebay)
it has 65,000 miles on it but also has 160lbs compression across the board. SOB runs like it used to and it will take me 10 years to wear this motor out.

 

First, I don't know anything about this swap... !
IF... I was doing it, I would check the gaskets against each other, see if the "round" cover the "square" area or vice-versa, so there are no leaks; should be metal to gasket on both sides and if the gaskets you use cover the ports on the heads and the headers and if all else works then I would use the heads that are on it.

I would keep the new 3.0L together as much as possible, when you start swapping things... THINGS go wrong.

Luck to ya !

Ltr

 

2000 Taurus could have a 3.0l OHV Vulcan engine, like Rangers had, OR..............3.0l DOHC Duratec engine, which Rangers never had

3.0l Duratec used different computer and wiring, and different heads

3.0l Vulcan engine used the same heads and exhaust ports in the heads, in Taurus or Ranger, so Ranger exhaust manifolds will bolt to Taurus heads, so you may not have a 3.0l Vulcan engine

In a car the 3.0l Vulcan head gaskets were different because engine was mounted sideways(transverse) so the coolant flow thru the heads was back to front
In a Ranger the flow was front to front
So you should change the head gaskets to the Ranger models

3.0l OHV Vulcan engine rebuild guide here: https://www.therangerstation.com/tec..._0-build.shtml

Shows all the changes over the years to the 3.0l Vulcan, applies to cars, vans and trucks