Hi John, I picked up the 2 new additions to the 744 stable today. I have measured and come up with the following. My restored 744 S/ N 1383 manufactured in 1949 has the large cut out bonnet and a wheel base of 2000 mm, the 2 newer additions have the S/ N 2887 and 12124. Both have the smaller cut out bonnets, but S/N 2887 has an 8" longer wheel base. So, in conlusion, it appears as though the changed the bonnets style in 1950 regardless of the wheel bases... Interesting!!! I do know for fact that my early restored tractor had the English wheels like the one is just picked up, but the middle tractor has the standard Australian heavy vast wheels. I will try and add some pics for you. Regards Buck