I'd have to pull out some books to see exactly what was what, but I can say this much without doing so....there was a change in engine blocks in later production, if I recall correctly 28000? was where some big changes took place in the series, now whether the blocks changed at that point or not I can't say without looking into it. My advice would be spend some time on Jdparts.com and do some comparisons.
As for eliminating the pump and drive on yours, there will be oil flow ported for the pump and drives, so removing them will effect that, possible one could block off the galleries, but one would have to make sure it wasn't effecting things somewhere down the line. Also could effect lube of the actual front gears themselves.
I imagine it can be done. Have to admit I am wondering what happened that it ate the gears in the first place...
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