STOP with the door handles, spare tire, and reliance on the perspective challenged Z Film. None of that comes close to actually resolving this age old issue. I'll give you a hint and then wait to see if you are worthy of being called a JFK Assassination Researcher. Go back to the very Beginning. You know, Love Field. The principles were filmed boarding and then selecting where they sat down inside the JFK Limo relative to each other. You can even see inside the Limo with respect to the placement of Gov Connally's jump seat. There's also footage from the rear of the JFK Limo pulling away. Now, Chop, Chop!