'93-'95 was the Series 6 Tranny and ... well, it kinda sucks

'96-'99, so I hear, is the mighty and improved Series 7.

'00-'02, I'm to understand, i the Series 8, which is the same as the Series 7.

Then, there's the RZ almighty tranny which was all the awesomeness of the Series 8 with a harder, smaller 5th gear for lower RPM's in OD.

So... here's the question:

How can you tell the difference, from the outside, of all these different sub-generational transmissions?

I'd LOVE to buy an RZ tranny for my 7 but how do I know I'm getting what I'm buying?

So, if anyone knows the diff (driveline humor) between these transmissions by sight and detail please inform me. Thanks... 'cause searches as yielded nothing ... so, either I'm a shitty searcher or this enigmatic question has yet to be broached. I'm hoping the latter so I don't look like a doofus.

 

I believe the later ones used double-cone synchros on fewer gears than the earlier ones. Also of course the 5th ratio was a bit different.

Not sure why the series 8 would be much better than the series 6 - the bearings and vast majority of internals are identical. I'd like to tear down a series 8 for comparison.

David