Hi cephas,
Great to see that you have your project on the move!
Mate, as far as the 'this or that' is concerned; you have 2 genuine Scott Bonnar Model 33's (as per your ID plate attached to each mower). I am led to believe that these were the forerunner of the popular Model 45 and share some identical features. As for the "Lawn King" which appears to be a Model 33 with a different colour paint job and badging, may have been produced by Scott Bonnar for a particular reason... eg. a company such as David Jones or Myers; for export to say New Zealand or some such.....unfortunately records are scarce and the now parent company Rover can't supply any info on the early days of SB
Hoping this might throw some light on the matter.
