In a city where car enthusiasts abound, the first-ever Mustang Rally car show roared into the heart of Laredo on Saturday, drawing a vibrant crowd to celebrate Ford’s iconic muscle car.

It wasn’t built to be a boulevard cruiser or a poser’s muscle car. The 1969 Mustang Boss 429 came to play hardball.

Ford sold over 7,000 Boss 302s in 1970, but only 305 examples were painted Calypso Coral and fitted with this specific ...