I spoke with Tom tonight and I find him to be very pleasant and knowledgeable regarding Ford engines and transmissions. Tom is VERY happy with his engine and transmission and excited to learn more about his unique setup.
As you all suspected, Tom has a light truck 390 (TE) from the early 70's. His stroke is longer than 3.5" which makes it a 390. Remember, 390s and 427s used the same Crankshaft; the only difference is bore diameters. FE parts were designed to be interchanged with the goal of making your engine specific to your application be it for car, boat, construction equipment, etc.
Truck pulleys and T-bird pulleys are different lengths. His engine and heads were truck, and the timing cover, pulleys and final dress are T-bird or Galaxie. That would explain why his Expansion Tank looks different, with the fill neck off to the side instead of on top.
Tom is very impressed with how smooth his engine runs. To me, that indicates someone did a good rebuild and not too long ago.
Tom's Fuel Pump broke. The parts counter guys couldn't find the correct part (for a Squarebird engine). They went through the years and found it matched a '72 Fairlane. That confirms our suspicions as his Timing Cover has the Fuel Pump mounting holes in a lower place.
John, I read that about the "flame hardened" valve seats. The problem isn't just the seats. It's also with the valves. Modern cars use stainless valves which cannot weld themselves to the seat material. I showed one pic of the '73 TE head. To pass fair judgment here are the remaining nine with a pic of both heads:
I don't know how anyone can 'harden' nodular cast iron because it has over 2% carbon and no grain structure. It's already so hard it's brittle. They chipped off core 'flash' with air hammers at the Dearborn Iron Foundry. Dozens of workers worked on the Chipping Lines and pieces of iron chips went flying everywhere. Everyone gladly wore ear muffs and safety goggles. I remember one guy's job was to stick a board in a bore and flip the blocks over as they traveled to the next guy.