You are correct in your assumption, those reliefs are for the injector spray. While it is not absolutely necessary to add them to the "round" port head, it would be best to. And as you say, it is easy to do in the way you described. I've done it and the aluminum is soft and easy to shape. In fact I'd suggest not using a carbide burr, as it is a bit aggressive for this. I used a sanding drum or scroll to add the shape, it will go quickly.
Completely agree. In fact by the time I was done port matching the head and intake manifold the size of those scallops became smaller. That's because I found the Fiat head and manifold ports to be pretty far off one another, making the openings larger by the time they were aligned. That larger opening meant it came closer into the scalloped recess already. Therefore I suggest doing the port matching first, then add the scallops.
The wrist pins are "fully floating," not a press fit; there are wire clips in a groove on either side. (They're not easy to remove cleanly, if you plan to reuse)
Alex, I'm a little surprised your crank was so out of balance. I'm curious if any idea why it was? Had it been modified, machined, or otherwise worked on previously?
No idea of the history of the engine, I pulled it from a scrap uno turbo (after starting it to make sure it at least ran). I didn't notice it really until it got rebuilt by Guy Croft. He is the one who told me the crank was out of balance and got it, among other things, sorted for me.
