Red clay
#2
Have a lot of it here in Louisiana. Try original Dawn and scrubbing. Careful on color of carpet though. But I've never successfully truly gotten it all out when I got in vehicles. Maybe someone can chime in with better exp getting it out.
#4
Same here in NC. I usually pressure wash the outside and that works fine except for the soft top. Always seems to be some kind of residue left so I have convertible top cleaner or upholstery cleaner that I use with a small scrub brush.