The Syncro I bought last summer for my engine conversion had a bumb
engine.  When I was doing the plumbing for the Subaru engine, I found
that the cooland distribution box (which looked fine from the bottom)
was actually missing the top half and when I took it out, it crumbled in
my hand.

Lucky for me ( 1500$US engineless Syncro)
bad for the PO.

I would strongly recommend replacing with copper.  With the Subie this
distribution box isn't needed.

...Markus