The blue mule can be built using a resin cab and an Ertl International Transtar II kit as a donor kit
I built it, But, Didn't put any of the mule signs on it because this one was hand painted and also has pin stripes like the one's used on real cars on it
https://www.scalemates.com/kits/ertl-8017-transtar-ii-eagle--686345