I read somewhere that the photograph of a car on Gen Edwin Walker's car with the number plate cut out and removed was Hosty's car. A photo exists without the number plate removed but I think it can't be read. May be it can be determined with today's technology?
The fact that Hosty's number was in Oswald's book wouldn't have necessarily been a reason to cover up Hosty's car at Walker's home. That is unless of course he was up to a covert plan to frame Oswald as the shooter who fired at Walker. The range of that shot made it impossible for anyone who knew one end of a rifle from the other to miss. Walker was very right wing, Oswald was painted as a commie.
Was Hosty a member of any far right organisation?