Victor, Very limited info on TractorData.com which you may have found out. No serial number info. However with your engine info that you gave appears you have model SD, lever steer or model SUPER SD, steering wheel steer ?
There is a club www.gibsontractors.com which gives some info. Appears you have to join to ask questions.
There is also old posts here on Yesterdays Tractor that I found by doing internet search.
I imagine someone on here will come on with more knowledge once they see your question.
Good luck, Bill