I was just on the line with Shahzad (the owner of the workshop where the Impala is being rebirthed). According to him, we have a fire-breathing '67 Impala that lives, now!
From what I've been told, the engine is ticking along perfectly, Alhamdolillah, and all systems seem to be working fine, right now. Of course, the car is going to stay running overnight, so we detect any faults or foibles that might be present in it, and tomorrow it will be getting its road test, Insha Allah.
This has been a long time in the making! I just hope the road test turns out to be successful.