being a bit of a petrolhead, I was curious about that engine and whether it really was a diesel. In the bit of it that you could see in that half-picture, it looked rather nice.
I started with a picture of a truck but it didn't look right. Scale was off. Big car windshield... tiny truck cab. Then I found
this.
This is your pic only much smaller.

I'm not a gearhead (US version) but I grew up in a family that fixed what broke.
Back then it was mostly metal stuff held together with screws, nuts and bolts. Instead of todays plastic, rivets and Ultrasonic Welding.
Though one exception comes to mind regarding the old nuts 'n bolts vs. todays rivets. The factory installed ball-joints on a '63 Corvette are riveted on.
40 mins. turned into 4 hrs.
