[Jack21]

The parts are off the shelf. It just depends on whose shelf you look on. Perusing the Keith Craft site from this forum, he offers a "built" 393W short block (Scat crank, Scat rods, SRS or Probe pistons) for ~$400 less than the FMS short block, and an econo model, probably comparable to the FMS (Scat crank, stock rods, TRW pistons) for ~$600 less. He does complete crate engines too, built to your likeing.

Next to perhaps Jack Roush, Keith Craft is one of the foremost Ford engine builders nationwide, if not worldwide. Perusing his "What's New" section is his new CNC machine. Do you know what one of these jewels cost? Well into 7 figures. And his "Built individually at the North Pole by elves" prices are still less than a FMS production line, or low bid contractor assembled engine.

So, shop around.