In this episode, Rockford's Firebird switches between the original model with round headlights and the 1977-and-up model with twin rectangular units.
The pickup that blows up starts as a 1964 Chevy as it drives up. When it hits the rock and pothole and the scene shifts to the exploding truck the truck shown exploding is a 1961 Chevy.
When the police and Jim are waiting for the bomb squad to detonate the found explosives, the number of police cars in the background switches in consecutive shots. It goes from one police car to three police cars to just the bomb squad van.
It is stated Rockford and the murder victim, Reidy both served in the 5th Regimental Combat Team during the Korean War. Later, however, both Rocky and Rockford say there are 3,000 men in a battalion. A regiment does have approximately 3,000 soldiers. A battalion is a smaller army unit with approximately 1,000 soldiers.
The bad guy had a stockpile of weapons at his disposal.
He would not need to use Jim's gun or wait until it was discovered to carry out his murder plot.
When Rockford and Becker visit Lee Ronstadt's house for the first time, the boom mic's visible in the left corner of the frame as they wait on the porch to be let inside.