No! The word "completed" is yours. With the exception of Carter, the occupants do not provide any further details of how far they had turned.

You sound like a petulant child.
If you don't like the word "completed" then choose another word that means the VP security car has finished turning and is now travelling on Elm Street. You refuse to accept what the witnesses are actually saying. If they were still in the process of turning they would be saying things such as "as we were making the turn" or "while we were turning"...but they don't.
The all use the past tense of the verb "to turn" indicating the process of turning had been (I'd better not use the word "completed" as you seem to have a problem with it)...finished.
When Rich says "we turned off of Houston Street onto Elm Street" you need to believe he is saying they are still in the process of turning. But he's not, he's saying that, at the moment of the first shot, the VP security vehicle had turned off Houston Street and was now on Elm Street.
When Carter says "...our car had just made the left hand turn onto Elm", he's not saying they were still in the process of turning. He is saying that the turn had been "made". The turn had been done. The turn was over. It was...(I shouldn't say it)...
COMPLETED!!You cannot escape this evidence. All you can do is try to obfuscate and misrepresent.
We've been here before and I know from experience there is no point carrying on this debate.
Normally, on a 90 degree turn, if you make a turn off one street onto another you are very close to completing the turn. But not this turn onto Elm which was a 120 degree turn. Carter described the security car being along side the TSBD. I suggest that means the car was turned 90 degrees, not 120, so that it was parallel to the TSBD front.
When you wrote - "According to Carter, they had only turned 90 degrees." - I knew you were "untruthing" yet again.
You put those words in Carter's mouth but it turns out he said nothing of the sort. Instead it turns out to be some kind of perverse logic on your behalf. No surprise there.
The Tyler mapping program shows that at z195 the VP security car is still in the process of turning off Houston and onto Elm. This demonstrates that the first shot did not occur at this point.
I know you won't accept this and that you will just try to twist the evidence beyond reason, as you have already done.
The rest of your post is just the usual nonsense and not worth dealing with.
A first shot at z195 has been refuted.