no probs
under valued axles by all apart form Australians
work quite nicely with a LSD/sure grip cone centre
the 25 spline axles open centre works fine provided you don't do burnouts
The Cortina and escort boys spend a fortune building up their standard axles
when the aussies had a standard M75 one that worked behind a nice big six cylinder
and GM used the M78 as a heavy duty axle in the Camaro/firebird
those cars got a mix of 10 bolt dana 44 and M78
the US chevy guys call the M78 a GM 9 bolt
RATECH in the us do rebuild kits as well all the shims and spacer you need
www.9bolt.com supply aussie parts to US customers
I'd just get my parts from Australia but 9 bolt.com has some nice detail
Geoff Houser built up mine, the process to build is much like a dana
The M series axles were made by BorgWarner who were taken over by BTR (brtitish Tyre and rubber) who were taken over by Spicer Axle
axles made from 6 inch to 9 inch ring and pinion
anything that fits a Vl-VS holden commodore fits an M75 M76 or M78 provided you swap to SAE28 spline axles.
Dave