Good morning brocky05 and welcome to the ODK forums.
The model reference number above is for the engine rather than the ride-on. Based on the code 78062311, the first 6-digits identify the year of motor in YYMMDD format as being 23rd June 1978.
Does the diff/transmission have any identification numbers on it, as this will help you get the specific manual for the equipment?
Being so old, not sure if there will be any label left to identify your specific ride-on model, unless it has a number stamped on the chassis somewhere that may help.
