What is this front end from?

Clever customizations. That is a popular branch of the auto hobby. If your cup of tea is museum restorations, I respect that too. Imagine the effort that goes into designing these mods. Wouldn't anyone be proud driving that Barracuda?

Instead of molesting a fine car, these guys might have been repairing damage from a wreck or corrosion. I think it is smart when people can find junkyard parts to adapt. The extreme are "rat rods", where people purposely make them look worn or cobbled together, and those are clever too.