I'm not Lloyd, but I'll tell you what I know. There are some who recommend Prolong Super Lubricants, transmission additive, delet recommended volume of Fluid, and add the Prolong stuuf, for volume equalization.
Takes a pretty big Allen wrench to do the job, but 3/8" drive tool is available through Pantera Vendors. Pantera International has their entire catalog on-line. They have a great publication too, and I just re-newed my subscription, because these people have been good to me and I like the publication. Have a stack of them, never thrown one away and use them for reference.
I want a Butfoy 6-speed ZF (polished) someday, sorry Lloyd, for cutting in here, it was your question....
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