It was a visit to the North Devon County Show that inspired me to knit a vintage tractor. You can read about it hear. http://ginxcraft.blogspot.co.uk/2014/08/devon-county-show.html The rows of vintage tractors looked so cute, and much nicer than the modern ones.
I have tried really hard to be realistic with my tractor, but as a result this is not an easy knit. There is cabling on the large rear wheels, and some colourwork on the front grill, and a tiny bit of icord knitting for the chimney and steering wheel. But I think the results are well worth the effort. All the pieces are knitted flat, and there is quite a lot of sewing up.
I have used Patons Diploma Gold DK, as I thought the colours worked well, but other DK wools will also work.