Ok it's a bit hard to explain but during assembly, the engine number takes on whatever chassis it goes into, regardless of where the engine was made. In your case, it's a truck chassis assembled here from US-made parts. If it was cast in 77, it's a local block. Around that time, we were starting to export the blocks back to the US for NASCAR use, so they were well and truly used up over there. Another example: My Cortina engine number started with "CG58" as that's what a Cortina chassis came with, despite the engine being a locally made 6. C = Great Britain G = Geelong assembly 58 = Cortina 6-cyl GL sedan Any clevo will bolt straight into any vehicle that had a Clevo as an option. In my case, an XB ute engine ended up being rebuilt for someone's F100 which was never installed but sold to me to go into my XE wagon. See what I mean? A lot can happen in 40-odd years so it's no surprise that your block ended up in a Falcon. Sent from my CPH1607 using Tapatalk