The VIG1 was a tractor manufactured by David Brown Engineering Limited for use by the RAF as an aircraft/supply tug during WWII and well into the 50's.
1/72 versions of the tractor can be found in the Airfix Short Stirling kit from 1966, and the WWII RAF Bomber Re-Supply Set (A05330) from last year. A 1/76 diecast version is also produced by Oxford.
I am currently assembling both old and new Airfix tugs, having picked up an old Craft Master (MPC) Short Stirling at a good price.
The instructions from the old Airfix kit are rather interesting, with detailed assembly instructions written out.
Curiously enough, even though the parts are numbered in the assembly diagram, the sprues do not have any corresponding numbers on them. I'm not sure if the currently produced Airfix Stirling still lacks numbers, but there was one part (223) I had a real difficult time finding.
A comparison of some of the parts are shown below. The tug from the Stirling kit is in white plastic, while the one from the Bomber Re-Supply kit is in gray.
Overall, the two kits are almost identical in size. Dimensionally, the two major differences are the fenders and the front wheels. The fenders on the old Airfix kit are almost 1mm wider than the fenders on the new kit (making the tug appear almost 2mm wider). The front wheels on the old kit are also almost 1mm larger in diameter.
Finally, a comparison with the Oxford diecast model of a tug in RN Fleet Air Arm colors.
The Oxford model is almost identical in size with the new Airfix model. It might even be a hair longer. Obviously there is something off with either the Airfix models, or the Oxford model. The tugs are about the size of a jeep, and I can tell the difference between a 1/76 and 1/72 scale jeep very readily. Not so with these models. They are either all 1/76, or all 1/72, but since they are consistent in size I wont complain too much.
In my opinion, the new Airfix kit is the most accurate looking, with superior detail. The old Airfix kit is the most simplified, with some oddities, like a mesh front grille. The Oxford model falls somewhere in between.