Another CV/axle question - 72 915 with later trailing arms

[profblue]

have read most threads on the forum, but still not clear in my head: I'm currently "right-dating" my 1973 T, which has been frankensteined to sth resembling a 993 and serving as a parts car which I bought as a rolling shell (don't ask for pics ).

Now, the PO changed some of the original parts out, which I consider actually an upgrade and tend to keep: one of these are alu rear trailing arms from 75.5-85.5, with the 6x8mm bolt flanges.

My gearbox is a year-correct 915/51, so before I pull the trigger on a complete 72/73 CV/axle/flanges, I wanted to check how the full set-up would actually work:

Reading Gary's great clarifications & posts on the forum, I understand the original axle has 4x10mm+2 pin working perfectly on the gearbox side, but on wheel hub side have need to connect with 6x8mm smaller flange.

Hence, my questions:
1) Can I change the outer CVs on the axle to the later style? I think NO, as I see that the axle spline OD is different (27 vs 30)

2) Using the 72 flange into the newer AL arm and rear wheel hub doesn't work, as the coarse vs fine style won't fit, at least that's what I understood. Therefore, can I change both rear wheel hubs to the earlier style (PN ) into the aluminium traling arm, so I can use the full 72/73 transaxle, with old style flanges? The axle length should be the same as far as I can tell.

3) Last noobie thought: retap 8mm to 10mm on both sides?

4) Other options - ideally full Porsche OEM and not $$$ intensive?
Should I rather look for another axle?

Thanks,
Martin

[Flat6pac]

I have an 10 mm bolt. 2 pin outer if needed
All 915 through 77 model year are coarse spline inside the trans.
Bruce