Saying they are focusing on the blue Gremlin, to the exclusion of every other car witnesses saw in connection with other body drop-offs in this case is like focusing on the last photo of Tim seen alive in his blue shirt. Science fair winner, hours before he was abducted, held captive for six days and then murdered.
Does it help? Not really. And yes, to the observant viewers who have noted this in the past: his finger nails are long and they are dirty. Just like my Mom told the cops. Which is why it was so sick the autopsy showed they were cut and cleaned. Thanks for noticing.