I read your opinions with interest and as always on this subject, become increasingly confused by the never ending web of possible scenarios, motives, conspirators etc.
The 'cover up' comes from the top in my opinion. LBJ, Hoover, CIA etc.
Take any 'run of the mill' murder. In most cases you have a victim, a likely motive, at most 2 or 3 main suspects and where there is no immediate conclusion, an investigating team of police etc. The JFK murder required all of the usual ingredients to be diluted beyond belief to effectively cover the tracks of the true conspirators.
To do this requires long term maticulous planning, financing, media control, government involvement, dummy leads, witnesses with conflicting stories, rumours, more rumours, a few more rumours etc.
Who could achieve this level of deceit? Probably all the very people who benefitted most from the assassination. I believe we will never know the truth and to a great extent, we will only ever know what the powers that be want us to know.
Disinformation, drip feeding, evidence being witheld and ignored at the time, seemingly sloppy police work, etc. The perfect crime.
The countries top pathologists couldn't even agree on where the back wounds were, whether the throat wound was a bullet hole or the result of a trachaeostomy. Have you ever heard of anything so ridiculous?