G'day Shedlock, That box with the larger selectors would most likely have come from an early model RR or possibly a 101 and is what is called a "long throw" box. Yes, the gearshift lever is different to the flat one like you have and has a ball on the end, but there is still a flat spot on the side that contacts the reverse selector. I have just measured one up and the ball diameter is 15mm if that helps. I can post a photo up later if you like. Unfortunately I only have 1 of these so I cannot help you out there. Got about 10 of the flat type for the later boxes but only one of the older ones. Maybe someone will have one lying around that they could send to you.
Cheers......Brian
1985 110 V8 County
1998 110 Perentie GS Cargo 6X6 ARN 202516 (Brutus)
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