The Chassis is indeed a Mitchell Model S. This was Mitchells six cylinder offering for the 1910 - 11 seasons. The chassis number will give us a an exact fix on the year. There were three versions through this period. I found little more than what you have here retired from service as a farm saw mill trailer when I was still in High School and have spent the past 30 years piecing it back together. the lads are right, the engines for these are nigh on impossible to find, only one has ever surfaced . if you would like any other detailed information on these I'd be happy to help., please feel free to drop me a line. noeldpe@optusnet.com.au Noel