Funny how things happen sometimes.
I've had this idea swirling around in my head for a while, and finally started working on it.
I tried arc welding aluminum with special rods, and didn't have any luck. Brazing went ok, but was really ugly. (technique was definitely suspect!)
So I gave up and took the manifold and pieces to a friend whose nephew is accomplished at aluminum MIG welding. I'd seen a bunch of his work, and it was good.
While explaining how I wanted it all put together, his son wanders over. Upon seeing what I had, he immediately offered me the use of his TIG welder to do it myself, noting that he "never uses it anymore."
...
never?
I asked if he wanted to sell it. After a few stunned-looking blinks, he replied yes. So now I'm the very proud owner of a new TIG, and the rest is history!

After 5 mins of chasing a puddle around a piece of aluminum, then finding I was able to stick a piece of aluminum plate to cast, I tackled the manifold idea.
Brickyard! Do you remember this badboy?




It's an ADG 1.9L n/a manifold, with a couple mods.
I removed the side inlet and capped it.

then cut off the front face.

The inlet pipe is close to the valve cover for hood clearance, and therefore had to be removeable. Two 3/8" plates became flanges, and the cone's taper 'bells' out through them to match the shape of the manifold's cut front face.
This manifold, the matching exhaust manifold and head are now enroute to Extrude Hone for dolling up.
Should flow a little better!