Hi Grumpy, I'll ask the question. In the end I posted a question on the B&S Facebook page and got some good contact information from the UK B&S guys which put me in touch with guys in the US. I've also posted some questions on the Greenfields Facebook page as I would still like to find out the date of my mower and also the colour it was finished in. As a matter of interest this is the Greenfield reply that I've had so far:
Wow Ron, thanks for sharing this old girl with us. The machine is called a Greenfield HD-8 Tractor, there were a few models within this style. They started with either a Honda or a Fuji HD engine pre 1970, it wasn't until about 1970 that they started making them with the Briggs and Stratton Engine and painted them Red. So you are looking at a machine that is the best part of 42 years old! Not bad for a Ride On Lawn Mower!!
So at the moment I'm a little bit unsure of the mower's date given that B&S engines were only started being used around the 1970s but my engine is 1960 and it would seem unlikely that the engine would have been replaced with one 10 years older!
