One in front. There was a hole in the windshield.
Read Lee and Me. It fills in all of the missing pieces.
There was no hole in the windshield. There was a dent on the inside window frame indicating a shot from behind.
3 shooters min. The kill shot was from the front, in his forehead. It blew the back of his head off. Any shooter should know this. Small entry, big exit. Not rocket science here.