Hi, Tommybrk.
Thank you for your kind comments on the article.
I have never had to go into that bottom gear box and I don't have any manuals so I am almost as much use as a breast pocket inna G-string or an udder onna hen.
I would not be at all surprised though if one of the members here with a more substantial library can help with that.
Just my 0.02.
You have a wonderful day. Best wishes. Deas Plant.