After some disassembly, I figured out why the fuel pump on my FC150 was puking gas everywhere.
The top section (circled in blue - stock photo) has a flawed casting, resulting in a huge crack, some deformation, and a bunch of other small cracks 😑. I'm debating various forms of JB Weld problem-solving, but I ordered a new one. The rest of the pump is fine, this is just the top section, but you can't buy just that part. It's doubly sad, because it looks brand new (installed by previous owner). By some bizarre alignment of stars, there was a returned unit on Amazon Warehouse for $65 (otherwise they are $100). I took a gamble on it. The best case scenario is that it's good. The second best case scenario is that the part I need is good. Otherwise I'll return it and drop the $100 on a new one.
One step forward, seven steps back.