Clinton 9hp question

[Dropkick66]

I just bought a Clinton 9hp k900 5000d and have no info on the oil fuel mix ratio, looked the internet over and over and so far this is what I found..
16:1 , 24:1, 50:1 my results are all over the board.. Can anyone shed some light on what ratio to use???

 

[steelespike]

K900, 10.14 cu in.9 hp at 6000. 48:1 for all motors bigger than 5.76.J13Y plugs at .025 gap. Torque, al Rod 35-40 in lbs Steel rod 70-80,crankcase bearing plate 75-95
Al,flywheel 400-450,Iron with steel keyway insert 375-400.reed plate and carb 60-65, spark plugs 230-270, stator plate45-65.

 

[Dropkick66]

Hey thanks a lot! One more question, should I run non ethenal premium or regular pump gas?