Why is there blue paint on the floor pans but it appears to be painted a desert tan metallic or similar?
It is not painted a factory original color. Many '51 Js, many, were originally satin blue and based on the engine compartment firewall, trunk floor and fading on the passenger side upper quarter, I'd say this one was originally satin blue too.
Whoever changed the color took the time to also do the insides but did not take the time to pull the engine and do the engine compartment. Can't say I blame them as that is a lot of work.
Regardless, it looks like a nice workable example and would make a fun car for someone. Original floorboards too - that's rare in any Henry J.