I thought I'd post a quick update. . .
I decided to purchase new 108mm, (6) 10mm bolt, G-50, w/end cap, CV joints to replace the inner CV's on my '74 axles. Here's the PN: 911-332-923-01-M60 and here's a photo from the Pelican catalog:
It looks like they will work in that the splines seem to be identical in their pattern as well as depth when compared to my '74 CVs.
So here's my entire axle assembly out to in:
'74 stub axle, '74 108mm outer CV (4-10mm bolts & 2-pins), '74 half shaft, G50 108mm inner CV (6-10mm bolts), G50 drive flange machined to fit in a 915 w/OS Giken LSD.
I haven't assembled everything yet, but it's looking like it will all fit together.
The only issue I am dealing with at the moment is the stiffness of the new CV joints. They are almost impossible to move by hand - is that normal? I posted in this thread about it as well:
http://forums.pelicanparts.com/porsche-911-technical-forum/578737-cv-joint-issue-2.html#post5880613
Tom